Appendix 14.A. Topographic Data for Hydraulic Models

SINCLAIR KNIGHT MERZ PAGE 91

Appendix 14.A. Topographic Data for Hydraulic Models


Table A.14 - Spatial Data Used in the Floodplain Model Construction

Data Description Use

PCC 1m contours 1m contours for Porirua urban areas

showing elevation

Contours supplied to PCC from Terralink

International Ltd, 26thJuly 2005

Contours were captured using

Photogrammetry with ground control and

generally have an accuracy of +/- 1m

Data won’t account for recent earthworks

in major subdivisions

Primary source of elevation data for

the floodplain DEM for the Mike21

component of the hydraulic model

Delineation of sub-catchment

boundaries

PCC 5m contours 5m contours for Porirua rural areas

showing elevation.

Contours supplied to PCC from Terralink

International Ltd, 26thJuly 2005

Contours were captured using

Photogrammetry with ground control and

generally have an accuracy of +/- 3.5m

Contours are recorded as being 98%

complete and data won’t account for

recent earthworks in major subdivisions.

Secondary source of elevation data for




boundaries

PCC Rural Aerial Photographs Colour aerial photos of Porirua rural district

Photos were flown in February 2005 at

1:2500 using a colour camera

Accuracy of photos is generally +/-7.5m

but worse in hilly areas

Delineation of modelled stream

channel

Model background

PCC Urban Aerial Photographs Colour aerial photos of Porirua urban

district using r27 series and r26 series tiles

Photos were flown by NZAM Ltd. in

January 2009 at 1:500 using a vexel

colour digital camera

Accuracy of photos is generally +/-1.3m

but worse in hilly areas


channel

Model background


Appendix 14.B. Rainfall Isohyet Report

B.1 Introduction

Meteorological and hydrological analyses were undertaken to provide up-to-date information for input to road drainage and waterway crossing design.

In 2008 SKM updated the 24-hour storm isohyet maps for the Kapiti Coast District Council. This report presents the data and analyses carried out to extend these isohyet maps south to Wellington.

The study comprised:

Collection of daily and sub-daily rainfall data recorded at all the rainfall stations in the study area

Analysis to determine period and completeness of the rainfall records

Extraction of daily, and where data is available 24-hour, annual maximum rainfall depth time series for each rainfall record

Determine suitable factor to adjust daily rainfall maxima to 24-hour maxima

Regional statistical analysis of annual maximum 24-hour rainfall to determine rainfall depths for return periods of 2, 5, 10, 20, 50 and 100-years for all rainfall stations

Impact of projected climate change on return period rainfall for 2090 time horizon

Preparation of isohyet maps for each return period and current and 2090 climate change scenarios.

Analyses have been carried out to determine the temporal distribution of storm rainfall in the Region that will be used to disaggregate the 24-hour rainfall depths. Accordingly it was not required to analyse shorter duration rainfall as part of this study.


B.2 Rainfall Data

Daily and sub-daily rainfall data was obtained from the Greater Wellington Regional Council and from the National Institute of Water and Atmospheric Research, New Zealand (NIWA) CliFlo database. The stations are listed in Table B together with their location and length of record.

B.2.1 Selection of Rainfall Records

Analyses were carried out to determine the years and extent of missing data in each record. Annual maxima for these years were accepted if:

The maximum occurs at approximately the same time as at least one of the other stations in the area

Periods of missing data did not coincide with the maxima recorded at other nearby stations.

On this basis the number of annual maxima that could be used in the rainfall analysis was determined for each record.

Usually records with less than 15 years of data are considered too short for meaningful statistical analysis. This study is to extend the storm isohyets determined for the Kapiti Coast Region (SKM 2008) south to Wellington. Rainfall records with as few as 13 years of data were used in that study because of the poor distribution of longer records. These records now have 14 years of data and were retained in the dataset.

The rainfall stations listed in Table B are divided into northern and southern geographical regions. The boundary between the regions was set at the southern extent of the isohyets generated for the Kapiti Coast study coinciding with the rainfall station at Paekakariki Hill. This data was included in the regional analysis for both the northern and southern regions.

Table B1 - List of Rainfall Stations

Station Name StationType1

AgentNumber

Network Number

Location RecordLength(Years)

NumberAnnualMaxima Latitude Longitude

Northern Region Arawhata D 3461 E15012 -41.006 175.13 34 24

Kapakapanui P 3329 E05914 -40.926 175.163 14 14

Kapiti Island D 3144 E04891 -40.855 174.932 45 36

MacIntosh 59201 -40.917 175.309

Manakau D 3302 E05722 -40.72 175.216 35 34

Mangaone Transmission Lines P - E05813 -40.836 175.170 14 14

Mt Holdsworth Lodge D 2460 D05944 -40.908 175.476 24 15

Oriwa P 3305 57302 -40.750 175.349 18 15

Otaki 1 D 3296 E05711 -40.764 175.145 77 72

Otaki East D 3299 E05714 -40.76 175.169 13 (12)0

Otaki River at Depot D/P 7362 E05716 -40.770 175.144 26 20

Otaki Temuera St D 3298 E05713 -40.76 175.134 16 14

Paekakariki Hill D 3341 E14091 -41.018 174.98 54 52

Paraparaumu Aero D/P 3145 E04991 -40.907 174.984 59 57

Paraparaumu Aero Aws D 8567 E04994 -40.907 174.984 52 52

Reikorangi D 3327 E05912 -40.903 175.11 35 31



AgentNumber

Network Number



Northern Region Taungata P 58201 -40.812 175.255 16 14

Te Horo Longcroft D 3308 E05811 -40.817 175.148 40 39

Te Horo, Jonelle D 7387 E05717 -40.79 175.158 17 15

Titahi Bay T. Plant D 3353 E1418F -41.114 174.817 17 (9)0

Waikanae Waterworks D/P 3307 E05802 -40.889 175.072 38 37

Warwicks P 3322 E05907 -40.957 175.077 28 24



AgentNumber

Network Number



Southern Region

Blue Gum Spur P 150010 -41.048 175.019 29 16

Makara 3386 E14273 -41.253 174.694 21 21

Mill Creek Reservoir P 141812 -41.148 174.796 24 19

Paekakariki Hill D 3341 E14091 -41.018 174.98 54 52

Putaputaweta P 150006 -41.012 175.005 7 (6)0

Seton Nossiter Park 142811 -41.210 174.816 18 14

Taupo Stream at Whenua Tapu 140806 -41.056 174.875 19 18

Wellington Aero D 3445 E14387 -41.322 174.804 11 (11)0

Wellington Buckle St D 3431 E14370 -41.3 174.783 7 (7)0

Wellington Glenside D 3401 E14287 -41.208 174.811 7 (7)0

Wellington Kelburn Aws D/P 25354 E1427P -41.285 174.768 4 (4)0

Wellington Newlands D 3400 E14286 -41.233 174.817 4 (4)0

Wellington Newlands D 3402 E14288 -41.229 174.827 2 (2)0

Wellington Rongotai D 3444 E14386 -41.321 174.801 13 (13)0

Wellington, Bowen St D 3389 E14276 -41.283 174.783 2 (2)0

Wellington, Karori D 3392 E14279 -41.284 174.737 2 (2)0

Wellington, Kelburn P 3385 E14272 -41.286 174.767 50 48

Wellington, Knowles Obs D 3383 E14270 -41.283 174.783 7 (6)0

Wellington, Thorndon D 3391 E14278 -41.283 174.783 16 16

Linden D 3355 E14181 -41.181 174.831 33 30

Belmont D 3365 E14191 -41.167 174.900 25 0

Tawa D 3352 E1418E -41.157 174.829 19 17

Judgeford D 3373 E14199 -41.123 174.941 31 22

Moonshine D 3473 E1510D -41.102 175.003 11 (8)0

Annual maximum 24-hour rainfall was extracted from the continuous pluviograph records using the Hilltop data management software used by Greater Wellington Regional Council. The output from this software provides the annual maxima and also identifies years where the data is incomplete and the periods of missing data.

The records for stations where data is read daily were analysed using custom software that extracted the maximum daily rainfall for each year of record and listed the periods of missing data together with the number of days with missing data in each year of record. Daily rainfall measurements are made at the same time each day whereas the 24-hour maximum rainfall can start at any time of the day. Accordingly, the daily maxima need to be adjusted to compensate for the fixed time span. For the Kapiti study (SKM 2008), daily rainfall was factored by 1.16 (obtained from work published by Dwyer and Reed in 1995). The suitability of this factor was reviewed by comparing annual 24-hour maxima and daily maxima for the continuous records. The results showed that the ratio between 24-hour and daily maxima varied between 1.00 and 1.77 with an average of 1.15. Accordingly a factor of 1.16 is reasonable for the region and was retained for this study.


B.3 Frequency Analysis

B.3.1 Frequency Distribution

Previous analyses (SKM 2003, SKM 2008) used the L-moment technique to identify an appropriate distribution for regional rainfall analysis for the Kapiti Coast Region. The analyses showed the Generalised Logistic distribution to be appropriate.

The analysis carried out in 2008 was based on 20 rainfall stations distributed between Manakau in the north and Paekakariki Hill in the south. Additional data has been obtained for some of these stations and another 11 stations have been included to provide data for the area south to Wellington. The L-moment ratio diagram showing the rainfall station data and weighted averages for the northern, southern and combined dataset is shown in Figure 45.

Figure 45 - L-moment Ratio Diagram

The plot indicates that either the Generalised Logistic (GL) or the Generalised Extreme Value (GEV) would be appropriate distributions for regional frequency analysis of the data sets. The GL distribution was selected in the previous analysis of the northern data set and was retained for both data sets to preserve consistency between the previous analysis and across the whole region.

The project area was divided into two regions because rainfall drivers differ between the Kapiti (northern) and Wellington (southern) regions of the project area.

0

0.1

0.2

0.3

0.4

-0.1 0 0.1 0.2 0.3 0.4

L-Ku

rtosi

s

L-Skewness

South Site Samples

North Site Samples

South Average

North Average

Combined Average

Generalised Pareto

Generalised Extreme Value

Generalised Logistic

3 parameter Lognormal

Pearson Type III


Regional parameters for the Generalised Logistic distribution were determined using the RegFreq software. The regional parameters were calculated as the average of the individual station parameters weighted according to the number of annual maxima in the respective record. These parameters are listed in Table 15.

Table 15 - Regional Parameters for the Generalised Logistic Distribution

Parameter Parameter Value North South

Location parameter ( ) 0.9625 0.9445

Scale parameter ( ) 0.1548 0.1641

Shape parameter (k) -0.1438 -0.1967

B.3.2 Estimation of Storm Rainfall

The Generalised Logistic distribution was used to estimate 24-hour storm rainfall for a range of recurrence intervals at each of the rainfall stations used in the analysis. These rainfall depths are summarised in Table 16. The values for Paekakariki Hill are the average of the values determined in the northern and southern region analysis.

Table 16 - 24-Hour Storm Rainfall Estimated Using the Generalised Logistic Distribution

Site Name 24-hour storm rainfall (mm) for Average Recurrence Interval (years) 2 5 10 20 50 100

Northern Region Arawhata 130.1 162.1 184.1 206.7 239.1 266.2

Kapakapanui 118.5 147.7 167.7 188.3 217.8 242.5

Kapiti Island 74.5 92.9 105.5 118.4 137.0 152.5

Manakau 71.4 89.1 101.1 113.6 131.4 146.2

Mangaone 96.1 119.8 136.0 152.7 176.7 196.7

McIntosh 225.1 280.6 318.6 357.8 413.9 460.8

Mt Holdsworth 106.6 132.9 150.9 169.4 196.0 218.2

Oriwa 248.9 310.3 352.3 395.6 457.7 509.5

Otaki 1 57.6 71.8 81.5 91.6 105.9 117.9

Otaki Depot 62.3 77.6 88.1 99.0 114.5 127.4

Otaki Temuera 70.1 87.4 99.2 111.4 128.9 143.5

Paekakariki Hill 84.6 106.7 122.3 138.7 162.9 183.6

Paraparaumu Aero 66.0 82.3 93.4 104.9 121.3 135.1

Reikorangi 95.9 119.6 135.8 152.5 176.4 196.4

Te Horo Longcroft 78.4 97.8 111.0 124.7 144.2 160.5

Te Horo Jonelle 77.3 96.3 109.4 122.8 142.1 158.1

Taungata 150.2 187.3 212.6 238.8 276.2 307.5

Waikanae 77.8 97.0 110.2 123.7 143.1 159.3

Warwicks 134.0 167.1 189.7 213.0 246.4 274.3

Southern Region

Blue Gum Spur 118.8 151.7 175.5 201.1 239.5 272.9

Judgeford 67.1 85.7 99.2 113.6 135.3 154.2

Linden 80.1 102.2 118.3 135.5 161.4 183.9


Site Name 24-hour storm rainfall (mm) for Average Recurrence Interval (years) 2 5 10 20 50 100

Makara 81.1 103.5 119.8 137.3 163.4 186.3

Mill Creek Reservoir 68.8 87.8 101.6 116.4 138.6 158.0


Whenua Tapu 63.8 81.5 94.3 108.0 128.7 146.6

Wellington, Thorndon 73.0 93.2 107.8 123.6 147.1 167.7

Seton Nossiter Park 65.4 83.5 96.6 110.7 131.8 150.2

Salamanca 74.2 94.8 109.7 125.7 149.7 170.6

Tawa 68.5 87.5 101.3 116.1 138.2 157.5

Comparisons were made between the storm rainfall determined for the 2008 update and the current study to assess the impact of additional years of data in some records and omission of three records that were previously used because of their record length. Storm rainfall depths increased by 3.5%, 2.3% and 1.6% for the stations at Warwicks, Manakau and Te Horo Longcroft respectively. For the other stations the difference is less than 0.2%.

B.3.3 Climate Change

The Ministry for the Environment published a guidance manual for Local Government in New Zealand for assessing the expected impact of climate change in May 2008 (MfE 2008). These guidelines were used to estimate the impact that climate change is likely to have on storm rainfall in the Wellington Region at 2040 and 2090 time horizons.

Percentage adjustments to storm rainfall per degree C change in temperature were obtained from Table 5.2 of the guideline and applied to the 2040 and 2090 projected increase in temperature for the Wellington Region of 0.9ºC and 2.1ºC obtained from Table 2.2 and Table 2.3 respectively. Factors for adjusting current storm rainfall to the 2040 and 2090 time horizons are listed in Table 17.

Table 17 - Climate Change Factors for 2040 and 2090 Time Horizons

Return Interval (Years)

2 5 10 20 50 100

Table 5.2 (adjustment to rainfall per 1ºC of warming) 4.3% 5.4% 6.3% 7.2% 8.0% 8.0%

Climate change Factor 2040 1.039 1.049 1.057 1.065 1.072 1.072

Climate change Factor 2090 1.090 1.113 1.132 1.151 1.168 1.168

Projected storm rainfall for the 2040 and 2090 time horizons were calculated using the factors in Table 17 and are summarised in Table 18 and Table 19 respectively.

Table 18 - 24-hour Storm Rainfall 2040 Time Horizon

Site Name 24-Hour Storm Rainfall (mm) for Average Recurrence Interval (years)

2 5 10 20 50 100

Northern Region Arawhata 135.1 170.0 194.5 220.1 256.4 285.4

Kapakapanui 123.0 154.9 177.2 200.5 233.5 259.9

Kapiti Island 77.4 97.4 111.5 126.1 146.9 163.5


Site Name 24-Hour Storm Rainfall (mm) for Average Recurrence Interval (years)

2 5 10 20 50 100

Manakau 74.2 93.4 106.9 120.9 140.8 156.8

Mangaone 99.8 125.6 143.7 162.6 189.4 210.8

McIntosh 233.8 294.3 336.7 381.0 443.7 493.9

Mt Holdsworth 110.7 139.3 159.4 180.4 210.1 233.9

Oriwa 258.5 325.4 372.3 421.3 490.6 546.2

Otaki 1 59.8 75.3 86.2 97.5 113.5 126.4

Otaki Depot 64.7 81.4 93.1 105.4 122.7 136.6

Otaki Temuera 72.8 91.6 104.8 118.6 138.1 153.8


Paraparaumu Aero 68.5 86.2 98.7 111.7 130.0 144.8

Reikorangi 99.7 125.4 143.5 162.4 189.1 210.5


Te Horo Jonelle 80.2 101.0 115.6 130.7 152.3 169.5

Taungata 156.0 196.4 224.7 254.2 296.1 329.6

Waikanae 80.9 101.8 116.4 131.7 153.4 170.8

Warwicks 139.2 175.2 200.5 226.8 264.2 294.1

Southern Region Blue Gum Spur 123.4 159.1 185.5 214.2 256.7 292.6

Judgeford 69.7 89.9 104.8 121.0 145.0 165.3

Linden 83.2 107.2 125.0 144.3 173.0 197.2

Makara 84.2 108.6 126.6 146.2 175.2 199.7



Whenua Tapu 66.3 85.5 99.6 115.0 137.9 157.2



Salamanca 77.1 99.4 115.9 133.8 160.4 182.8

Tawa 71.2 91.8 107.0 123.6 148.1 168.8

Table 19 - 24-Hour Storm Rainfall 2090 Time Horizon

Site Name 24-hour Storm Rainfall (mm) for Average Recurrence Interval (years)

2 5 10 20 50 100 Northern Region

Arawhata 141.8 180.5 208.4 238.0 279.3 310.9 Kapakapanui 129.2 164.4 189.9 216.8 254.4 283.2 Kapiti Island 81.2 103.4 119.4 136.3 160.0 178.1 Manakau 77.9 99.2 114.5 130.7 153.4 170.8 Mangaone 104.8 133.4 154.0 175.8 206.3 229.7 McIntosh 245.4 312.4 360.8 411.9 483.4 538.2 Mt Holdsworth 116.2 147.9 170.8 195.0 228.9 254.8 Oriwa 271.4 345.5 398.9 455.4 534.6 595.1 Otaki 1 62.8 80.0 92.3 105.4 123.7 137.7

Otaki Depot 67.9 86.4 99.8 113.9 133.7 148.8

Otaki Temuera 76.4 97.3 112.3 128.2 150.5 167.5



Site Name 24-hour Storm Rainfall (mm) for Average Recurrence Interval (years)

2 5 10 20 50 100 Paraparaumu Aero 71.9 91.6 105.7 120.7 141.7 157.7

Reikorangi 104.6 133.2 153.8 175.6 206.0 229.4


Te Horo Jonelle 84.2 107.2 123.8 141.4 165.9 184.7

Taungata 163.8 208.5 240.8 274.9 322.6 359.2

Waikanae 84.9 108.0 124.8 142.4 167.2 186.1

Warwicks 146.1 186.0 214.8 245.2 287.8 320.4

Southern Region Blue Gum Spur 129.5 168.9 198.7 231.5 279.7 318.8

Judgeford 73.2 95.4 112.3 130.8 158.0 180.1

Linden 87.3 113.8 133.9 156.0 188.5 214.8

Makara 88.4 115.3 135.6 158.0 190.9 217.6



Whenua Tapu 69.6 90.7 106.8 124.4 150.3 171.3



Salamanca 80.9 105.5 124.2 144.7 174.8 199.2

Tawa 74.7 97.5 114.7 133.6 161.4 183.9


B.4 24-hour Design Burst Isopleths

B.4.1 Current (No Climate Change)

Current: 2-year 24-hour Design Burst Isopleths


B.4.2 Projected 2040 Climate Change

2040: 2-year 24-hour Design Burst Isopleths


B.4.3 Projected 2090 Climate Change



Appendix 14.C. Flood Frequency Analysis

This Appendix describes the methodology for flood frequency analysis.

The GetDat software was used to carry out flood frequency analysis on the annual peak flow data for the three streamflow gauges.

Plots showing the General Extreme Value (GEV), General Logistic (GLO), Gumbel (GUM) and Log-Pearson 3 (LP3) distributions together with the input data are presented in Figure 46 to Figure 48 for the Pauatahanui, Porirua and Horokiri respectively.

Based on inspection of the plots the GLO distribution was selected for each of the data sets as most representative of the flood distribution. The flood peaks for the three catchments, based on the GLO distribution are listed in Table 1.

Figure 46 - Pauatahanui Flood Distributions


Figure 47 - Porirua Flood Distributions

Figure 48 - Horokiri Flood Distributions


Table 1 - Summary of ARI floods (Generalised Logistic Distribution)

ARI

(Years)

Peak Discharge (m3/s)

Horokiri Pauatahanui Porirua

2 26 39 32

5 43 52 44

10 55 61 53

15 64 66 59

20 70 70 64

25 75 72 67

30 80 75 70

50 94 82 79

75 106 88 87

100 116 92 93

200 142 102 109


Appendix 14.D. Calibration Results

D.1 Horokiri Catchment

When calibrating the HEC-HMS runoff flows with the observed flows it was found that two parameters required adjustment; SCS Curve Number (CN) and Ratio. The following parameters were determined from the three calibration events:

Event Ia (mm) CN CIA (%) Tc (hrs) R ST (Hrs)

Calibration A 5 60 0 2 0.65 3.7

Calibration B 5 78 0 2 0.65 3.7

Calibration C 20 80 0 2 0.60 3.0

Figure 49 - Calibration A

Calibration A provides a good fit for peak, total volume and hydrograph shape.

0

2

4

6

8

10

12

140

10

20

30

40

50

60

8:005 Jan 05

20:005 Jan 05

8:006 Jan 05

20:006 Jan 05

Rain

fall

(mm

)

Flow

(m3/

s)

Time

Precipitation

HEC HMS Runoff

Observed


Figure 50 - Calibration B

Calibration B provides a good fit for peak and a reasonably good fit for total volume and shape. It can be seen that the simulation slightly underestimates both the rising and receding limb of the hydrograph. This is possibly due to the significant baseflow component which is not being directly modelled.

Figure 51 - Calibration C

0

2

4

6

8

10

12

140

5

10

15

20

25

30

35

40

2:0015 Feb 04

14:0015 Feb 04

2:0016 Feb 04

14:0016 Feb 04

Rain

fall

(mm

)

Flow

(m3/

s)

Time

Precipitation

HEC HMS Runoff

Observed

0

2

4

6

8

10

12

140

10

20

30

40

50

60

70

80

0:003 Oct 03

12:003 Oct 03

0:004 Oct 03

12:004 Oct 03

0:005 Oct 03

12:005 Oct 03

Rain

fall

(mm

)

Flow

(m3/

s)

Time

Precipitation

HEC HMS Runoff

Observed


Calibration C uses a higher initial abstraction in order to accurately model the rising limb of the hydrograph. The peak and general shape of the hydrograph is fits well, the underestimation of the receding limb is possibly due to underrepresentation of rainfall in the catchment.

Using these three calibration events the following conservative catchment characteristics were set:

Catchment Ia (mm) CN CIA (%) Tc (hrs) R ST (Hrs)

Horokiri 5 80 0 2 0.65 3.7

Two validation events were simulated using the set catchment characteristics. We expected the validation events to be more variable, largely due to the fact that the rainfall for these events was more localised and therefore less likely to be well reflected, in both depth and/or distribution, by the surrounding rain gauges.

Figure 52 - Validation D

Validation D depicts an event that is essentially two events over a short period of time. It is shown that the first event is simulated reasonably accurately whereas the second event is overestimated. This overestimation is due to HEC-HMS simulating initial losses only for the first event and not the second as well as a possibility of an overrepresentation of rainfall in the catchment for the second event.

0

2

4

6

8

10

12

140

5

10

15

20

25

30

35

40

45

0:00

…

12:0

0…

0:00

…

12:0

0…

0:00

…

12:0

0…

Rain

fall

(mm

)

Flow

(m3/

s)

Time

Precipitation

HEC HMS Runoff

Observed


Figure 53 - Validation E

Validation E shows a simulation of a small event. It can be seen that the shape of the simulated flow is reasonable however it is difficult to determine if the volume of rainfall is accurately represented. This validation is poor but at least simulated flows are conservative. With the quality of the calibration events it is felt the calibrated numbers should stand.

D.2 Pauatahanui Catchment

When calibrating the HEC-HMS runoff flows with the observed flows it was found that two parameters required adjustment; SCS Curve Number (CN) and Ratio. The following parameters were determined from the three calibration events:

Event Ia (mm) CN CIA (%) Tc (hrs) R ST (Hrs)

Calibration V 5 73 0 1.7 0.65 3.0

Calibration W 5 55 0 1.7 0.65 3.0

Calibration X 5 73 0 1.7 0.65 3.0

0

2

4

6

8

10

12

140

5

10

15

20

25

30

35

40

12:0030 Aug 09

0:0031 Aug 09

12:0031 Aug 09

0:001 Sep 09

12:001 Sep 09

Rain

fall

(mm

)

Flow

(m3/

s)

Time

Precipitation

HEC HMS Runoff

Observed


Figure 54 - Calibration V

Calibration V shows a good fit for peak, total volume and shape. There is a slight under representation in the receding limb of the hydrograph possibly due to baseflow inaccuracies.

Figure 55 - Calibration W

0

2

4

6

8

10

12

140

10

20

30

40

50

60

70

8:005 Jan 05

20:005 Jan 05

8:006 Jan 05

20:006 Jan 05

Rain

fall

(mm

)

Flow

(m3/

s)

Time

Precipitation

HEC HMS Runoff

Observed

0

2

4

6

8

10

12

140

10

20

30

40

50

60

70

2:0015 Feb 04

14:0015 Feb 04

2:0016 Feb 04

14:0016 Feb 04

Rain

fall

(mm

)

Flow

(m3/

s)

Time

Precipitation

HEC HMS Runoff

Observed


Calibration W shows a good fit for peak however the shape of the observed flow is somewhat ‘fatter’ than the simulation. An increase in both CN and R could produce a better fit in this situation however a fit to peak only was viewed as acceptable.

Figure 56 - Calibration X

Calibration X shows a good fit in all aspects, peak, volume and shape, with only a slight preceding flow peak not becoming pronounced in the rainfall distribution.

Using these three calibration events the following catchment characteristics were set:

Catchment Ia (mm) CN CIA (%) Tc (hrs) R ST (Hrs)

Pauatahanui 5 75 0 1.7 0.65 3.0

Two validation events were simulated using the set catchment characteristics. Again we expected the validation events to be more variable due to the fact that the rainfall for these events was more localised and therefore less likely to be well reflected, in both depth and/or distribution, by the surrounding rain gauges.

0

2

4

6

8

10

12

140

10

20

30

40

50

60

70

80

0:003 Oct 03

12:003 Oct 03

0:004 Oct 03

12:004 Oct 03

0:005 Oct 03

12:005 Oct 03

Rain

fall

(mm

)

Flow

(m3/

s)

Time

Precipitation

HEC HMS Runoff

Observed


Figure 57 - Validation Y

Validation Y depicts a slight underestimation of peak and a slightly fatter shape in the runoff response. The observed response is also delayed. These differences can be explained by the rainfall not quite representing what occurred in the catchment both in terms of timing and rainfall peak.

Figure 58 - Validation Z

Validation Z shows an excellent fit with observed data only tending to be slightly conservative with the estimation of flow peak.

0

2

4

6

8

10

12

140

10

20

30

40

50

60

70

12:0020 Dec 82

0:0021 Dec 82

12:0021 Dec 82

20:006 Jan 05

Rain

fall

(mm

)

Flow

(m3/

s)

Time

Precipitation

HEC HMS Runoff

Observed

0

2

4

6

8

10

12

140

10

20

30

40

50

60

0:0023 Jul 09

12:0023 Jul 09

0:0024 Jul 09

20:006 Jan 05

Rain

fall

(mm

)

Flow

(m3/

s)

Time

Precipitation

Runoff

Observed


Based on the calibration and validation results we have decided to retain the calibrated catchment characteristics.

D.3 Summary

The calibration of design storm parameters is considered to be acceptable although it highlights the wide variability of runoff response that can occur from any given rainfall event. The rainfall depths estimate is likely to be the single greatest variable and in the future the analysis would benefit from more rainfall gauges in the upper catchments.

Initially assessed runoff volumes were in the right order of magnitude hence CN numbers only needed to be adjusted slightly however more storage exists in the catchment than had been previously assessed and hence storage R values were increased. Times of concentration were found to be calculated accurately as well as initial abstraction.

Final calibrated catchment characteristics used for the three catchments are summarised in Table 8.

Table 8 - Calibrated Model Parameters in HEC-HMS

Catchment

Name

Area

(km2)

Initial

Abstraction

(mm)

SCS Curve No Impervious

Area

Tc (hr) Ratio

Horokiri 28.7 5 80 0 2.0 0.65

Pauatahanui 38.3 5 75 0 1.7 0.65

Porirua 40.0 4 78 16 2.6 0.65


Appendix 14.E. Hydraulic Assessment Methodology

E.1 Introduction

This report describes in further detail the methodology, assumptions, sensitivity analysis, calibration and verification of the 1D-2D combined hydraulic modelling of the Pauatahanui, Horokiri and Te Puka/Wainui Streams.

E.2 Model Construction

E.2.1 Mike11 Base Model Construction & Assumptions

Using aerial photography the open channels within each of the study areas were schematised for the one dimensional modelling of the channel network. The dimensions and characteristics of structures and channel shape were specified based on cross-section survey data collected and supplied by Opus International Consultants (Opus) for this investigation.

Key structures such as culverts and bridges were represented in the 1D model using the software standard culvert/weir method. Where the length of the structure exceeded the maximum distance between cross-sections (dx max) the structure entrance was represented with a Mike11 culvert structure to take into account entry head losses and the remainder of the structure was represented by closed cross-sections. Inlet head loss coefficients for all modelled culverts have been based on the typical values as found in Austroads (1994), which provides standard entry conditions based on inlet design. For bridges the selection of the factor for the coefficient of contraction was based on the ratio of the bridge opening to the floodplain width. Typically on the constrained floodplains under investigation the contraction coefficient is between 0.1 and 0.3.

To model the effects of channel roughness, resistance values were selected based on the guidelines in Hicks &Mason (1998). The majority of the stream reaches have been modelled using Manning’s roughness coefficient of 0.035.

E.2.2 Mike21 Base Model Construction & Assumptions

The 2D model bathymetry was prepared from the best available topographic information at the time. The quality of the topographic data varied for each of the study areas but was generally either derived from LiDAR or high resolution contour information supplied by the local authorities including Kapiti Coast District Council (KCDC) and Porirua City Council (PCC). A summary of the topographic data provided is included in Table 20.

Table 20 - Spatial Data Used in the Floodplain Model Construction




PCC 1m contours 1m contours for Porirua urban areas showing elevation

Contours supplied to PCC from Terralink International

Ltd, 26thJuly 2005

Contours were captured using Photogrammetry with

ground control and generally have an accuracy of +/- 1m

Data won’t account for recent earthworks in major

subdivisions

Primary source of elevation data for




boundaries

PCC 5m contours 5m contours for Porirua rural areas showing elevation.

Contours supplied to PCC from Terralink International

Ltd, 26thJuly 2005

Contours were captured using Photogrammetry with

ground control and generally have an accuracy of +/-

3.5m

Contours are recorded as being 98% complete and data

won’t account for recent earthworks in major

subdivisions.

Secondary source of elevation data for




boundaries

PCC Rural Aerial

Photographs

Colour aerial photos of Porirua rural district

Photos were flown in February 2005 at 1:2500 using a

colour camera

Accuracy of photos is generally +/-7.5m but worse in hilly

areas


channel

Model background

PCC Urban Aerial

Photographs

Colour aerial photos of Porirua urban district using r27

series and r26 series tiles

Photos were flown by NZAM Ltd. in January 2009 at

1:500 using a vexel colour digital camera

Accuracy of photos is generally +/-1.3m but worse in hilly

areas


channel

Model background

Each of the three floodplains were modelled using a 5m grid. As the stream channels were simulated in the 1D model they were excluded from the 2D model to avoid the duplication of channel flows.

Aerial photography was used to classify floodplain resistance into four categories. Manning’s n values for each category were estimated using industry best practice and sound engineering judgement. Floodplain roughness values used in the 2D model are listed below in Table 21.

Table 21 Floodplain Roughness Values

Landuse Manning’s n Road 0.02 Trees/Scrub 0.15 Open Space/Pasture 0.035 Residential Areas 0.1


E.3 Pauatahanui Stream

The Pauatahanui Stream drains a catchment of approximately 42km2 on the eastern side of the Pauatahanui inlet. The catchment, shown in Figure 59, is bordered by the Collins and Ration Stream catchments to the north and the Duck Creek catchment to the west. The modelling investigation focussed on the catchment area surrounding the Transmission Gully Highway proposed alignment. This area is highlighted by the red square in Figure 59.

Figure 59 - Pauatahanui Catchment & Area of Modelling Investigation

The upper Pauatahanui catchment has numerous steep sided valleys which converge and drain northwest out onto the Pauatahanui floodplain. The total fall over the catchment is greater than 400m, with the peak elevation in the upper catchment in the vicinity of 450m above Mean Sea Level (MSL) and the lower catchment at MSL.

This hydraulic modelling investigation focussed on the lower catchment where the topography opens out from a gorge environment to the Pauatahanui Stream floodplain.

The upper catchment is predominately a mixture of rural pasture land and forestry. As the lower catchment opens up the land use becomes a mixture of rural pasture land, residential and commercial. The residential suburb of Whitby lies on the western boundary and at the northern boundary is Pauatahanui Village.

Crown Copyright reserved


E.3.1 Transmission Gully Project Main Alignment

The Project route through the Pauatahanui Catchment is shown in Figure 60. In relation to the chainages of the scheme design the section of highway located between Chainage 16,200 and Chainage 19,900 are within the Pauatahanui Catchment.

Figure 60 - Proposed Transmission Gully Alignment and Designation

A significant interchange is proposed between the Transmission Gully Highway and State Highway 58 (SH58). This interchange is intended to be located on the floodplain of the stream. Furthermore a “lay down area” to facilitate the highway construction and a weigh station are being investigated at this location. The interchange has been identified as a potential consenting “hotspot” on the proposed alignment, due to the significant footprint of the proposed road and its potential impacts on the Pauatahanui stream.

E.3.2 Pauatahanui Stream Model

The reach of stream channel that was modelled is shown in Figure 14.5. The hydraulic model starts adjacent to the sawmill on SH58 (Paremata-Haywards Road) and extends c3.4km downstream to the Pauatahanui Inlet.


Figure 61 - Modelled Reach of the Pauatahanui Stream

In the upper extent of the model the channel is located in a narrow steep sided gorge. The stream is constrained as it runs adjacent to SH58 until the topography levels out downstream of the Bradey Road Bridge. Downstream of Bradey Road the grade of the stream flattens out as it skirts the western perimeter of the floodplain before passing beneath SH58 at Paremata Rd and the Paremata Rd bridge adjacent to Pauatahanui Villages, and finally into the Pauatahanui arm of Porirua Harbour.

E.3.2.1 Topographic Survey

The lower reach of the Pauatahanui Stream is already crossed by four major structures. As shown in Figure 14.5, SH58 has two bridges while the other two bridges are located on Paremata Road (near Pauatahanui Village) and Bradey Road. The deck and soffit levels of all four structures were surveyed as well as the abutment locations.


Twenty-one cross-sections of the stream were picked up in the survey. The cross sections picked up the channel invert and spot heights between the true left bank and true right bank. Where possible a cross section was surveyed immediately upstream of the bridges to allow accurate representation of the channel at these hydraulic constraints in the stream model.

E.3.3 Pauatahanui Catchment Hydrology

For hydrological inputs into the hydraulic model the Pauatahanui catchment was divided into 10 sub-catchments (refer to Figure 62). The inflow from each sub catchment was extracted from the HEC HMS hydrological model as a discharge time series. Peak flows from the sub-catchments in both the pre construction and the post construction scenario are detailed in Table 22.

Table 22 - Peak Flows – Pauatahanui Hydraulic Model Hydrology

Catchment

Pre Construction Situation Post Construction Situation 10-Year Storm

(Q10)100-Year Storm

Including the Impacts of Climate Change

(Q100cc)

10-Year Storm (Q10)

100-Year Storm Including the Impacts

of Climate Change (Q100cc)

M11Paua1 86.1 197.7 86.1 197.7

M11Paua2 1.1 2.7 1.1 2.7

M11Paua3 0.7 1.7 0.7 1.7

M11Paua4 3.3 7.4 3.3 7.4

M11Paua5 1.5 3.6 1.5 3.6

M11Paua6 0.9 2.2 0.9 2.2

M11Paua7 1.0 2.4 1.2 2.6

M11Paua8 1.8 4.0 2.0 4.2

M11Paua9 3.2 7.3 3.2 7.3

M11Paua10 1.0 2.2 1.0 2.2

Total inflows 100.6 231.2 101 231.6


Figure 62 - Pauatahanui Stream Sub Catchments Calibration

The return period of the rainfall was determined by analysis of the rainfall gauges in the region. Calibration and verification of the catchment characteristics and storm shape in the hydrological model was undertaken based on analysis of specific rainfall events combined with the corresponding data from the Greater Wellington



Regional Council (GWRC) flow gauge at Pauatahanui gorge. The hydrological calibration is provided in Appendix 14.E. This analysis was used to develop the inflow hydrographs for the hydraulic model.

The analysis of the gauge data at Pauatahanui gorge indicates that the hydraulic model is likely to be overestimating the flooding for the lower order rainfall events. This is due to the storage in the upper catchment, especially in the area surrounding the golf course, which has not been included in the hydraulic model. However, due to the limited record period of the flow gauge it is difficult to determine if the hydraulic model is also overestimating the flooding in extreme rainfall events such as the 100 year storm event. In larger events the storage in the upper catchment is less likely to influence flows lower down. For this reason a conservative approach was taken and the inflows from the hydrological analysis were not scaled back to account for the storage in the upper catchment.

To provide further confidence in the hydraulic model the results were compared to the model results of previous flood studies in this area. In 2005 Connell Wagner completed flood hazard mapping for PCC on the Pauatahanui stream between the golf course on SH58 and the Pauatahanui Inlet. This work was prompted by flooding of a number of residential properties in January 2005. In this study a 1D hydraulic model of the stream was used to produce flood hazard extents for the 10 year and 100 year storm events without freeboard. As this model was only constructed in 1D the extent of the modelled floodplain was limited to that of the topographic survey undertaken. Because of this the mapping highlighted areas of “unidentifiable flooding”, or areas outside the model extent with the potential to be inundated by stream overflows.

As a coarse verification measure the predicted flood extents for the Transmission Gully investigation were compared with that of the 2005 study. This comparison was coarse as different modelling packages and methodologies were used in the two studies. However, the predicted flooding extents match well between the two studies. Where there are differences they can be explained by either the different approaches to modelling or the differing areas of investigation, as illustrated in Figure 63 and Figure 64.


Figure 63 - Comparison of Flooding Extents Between the 2005 Study and the Current Project: 100-Year Event


Figure 64 - Comparison of Flooding Extents between the 2005 Study and the Current Project: 10-Year Event

E.3.4 Sensitivity Analysis

To assess the impacts of changes in the model variables, a sensitivity analysis was undertaken on two key modelling parameters that could impact the results and alter the outcomes of the analysis. These variables were the downstream tidal boundary and the inflow hydrographs.


E.3.4.1 Tidal Boundary

The lower reaches of the Pauatahanui catchment are tidally influenced. A sensitivity analysis was undertaken to quantify the impact of assumptions in sea level conditions during the modelled storm events. The model of the 100 year rainfall event, with the predicted impacts of climate change (Q100cc), was run with a range of different tidal levels: 0m relative to Mean Sea Level (MSL) to simulate a lower level tide, 1m above MSL to represent an astronomical high tide (based on sea level gauging at Mana Marina, and a 2m tide above Mean Sea Level to simulate an extreme tide under storm surge influence.

The sensitivity analysis of the tidal boundary indicated that tidal levels in the Pauatahanui inlet were significant only on the peak water surface levels downstream of the bridge at Paremata Road. Figure 65 shows a comparison of peak water surface levels for a Q100CC year event coinciding with a 2m tide and the same event with a 0m tide. Upstream of the SH58 Paremata Rd bridge the tidal impacts on water surface levels are predicted to be very small. Downstream of the bridge peak water surface levels in Pauatahanui village were found to differ by as much as 600mm between the two scenarios.

Figure 65 - Comparison of Peak Water Surface Levels in the Q100CC Event with a 2m & 0m Tide

During the assessment of effects it was found that the potential impacts on flooding of the road construction were up stream of Paramata Road and therefore less influenced by the selection of tidal condition. With this consideration an astronomical high tide off 1m above MSL was selected for the remainder of the analysis.

Paremata Rd


E.3.4.2 Oversized Events

The hydraulic model’s sensitivity to hydrological inputs was tested by running an oversized hydrological event. The oversized event inflow hydrographs were created by increasing the 100 year flood event including the predicted impacts of climate change (100cc), by half again. The results from the oversized event and the 100cc

year ARI event were compared using the model of the pre construction situation. This analysis revealed that the predicted inundation extents in the oversized event did not increase greatly from the 100 year storm event but there were significant increase in the peak water surface levels. Water surface levels upstream of Bradey Road were predicted to increase by between 0.5m and 1m as were water surface levels in the pasture land upstream of the SH58 bridge at Paremata Rd. The lower catchment in the vicinity of Pauatahanui Village was predicted to experience increase in peak water surface levels of between 150mm and 300mm. This comparison influenced the selection of freeboard levels for the proposed bridge design.

E.4 Horokiri Stream

The Horokiri Stream drains a catchment of approximately 33km2 on the eastern side of the Pauatahanui Inlet. The catchment, shown in Figure 66 , is bordered by the Ration Stream catchment to the south, Kakaho Stream catchment to the west and the Te Puka Stream catchment to the north.


Figure 66 Location of Horokiri Catchment

The main stream channel begins at the Wainui Saddle and drains south out into the Pauatahanui arm of the Porirua Harbour. There is significant fall over the catchment with the peak elevation in the upper catchment in the vicinity of 500m above Mean Sea Level (MSL) and the lower catchment (at the southern end) at MSL.

In the upper catchment the steep sided valleys on the western catchment boundary are predominantly forested, whereas, on the eastern boundary the land use is predominantly pasture. As the lower catchment opens up onto the Horokiri Stream floodplain the major land use is rural pasture with pockets of residential dwellings. The majority of dwellings are located on the true right bank of the Horokiri Stream and have private access bridges crossing to Paekakariki Hill Road that runs on the true left bank of the stream.




The Transmission Gully Project route will traverse the upper Horokiri catchment as shown in Figure 14.16. The road alignment runs adjacent to the stream for approximately seven kilometres (scheme design chainages 5,300m to 12,600m) and will cross the main stream channel three times:

Bridge No. 4, scheme design chainage 8,450m

Bridge No. 6, scheme design chainage 9,720m

Bridge No. 8, scheme design chainage 11,750m.

In the upper catchment, the construction of earth fill embankments to support the new highway will require some permanent diversions of the main stream channel.

Figure 67 - Main Alignment in the Horokiri Catchment

Bridge No. 8

Bridge No. 6

Bridge No. 4


E.4.2 Horokiri Stream Model

The reach of the stream channel that has been modelled is shown above in Figure 66 and Figure 14.16. The hydraulic model incorporates c14km of the main stream channel beginning near the Wainui Saddle and extending down to the Pauatahanui Inlet. The hydraulic model also included a reach of the main tributary branch of the stream. This tributary drains the eastern catchment before draining to the main stream channel south of Paekakariki Hill Road. The majority of the modelled channel network is constrained by the steep sided valley topography of the catchment. Only in the reach c1.5km upstream of the Pauatahanui Inlet does the topography open out onto a wide floodplain.


The majority of the structures crossing the Horokiri stream are located south of Paekakariki Hill Road. Two major culverts pass beneath Paekakariki Hill Road and a triple box culvert passes beneath Grays Road near the stream mouth. The stream is also crossed by numerous private access bridges connecting residential properties on the true right bank with Paekakariki Hill Road on the true left bank of the stream. It was not considered practical to survey all the structures in the stream so only the three major crossings and 14 of the private access bridges identified as being significant hydraulic constraints were surveyed.

Thirty-four cross sections of the stream were picked up in the survey. The cross sections picked up the channel invert and spot heights between the true left bank and true right bank. Where possible a cross section was surveyed immediately upstream of a bridge to allow accurate representation of the channel at these hydraulic constraints in the stream model.

E.4.3 Horokiri Catchment Hydrology

To create hydrological inputs for the hydraulic model, the Horokiri catchment has been subdivided into 15 sub catchments (refer to Figure 68).The inflow from each sub catchment was extracted from the HEC HMS hydrological model as a discharge time series. Peak flows from the sub catchments in both the current pre and the post construction scenario are detailed in Table 23.

Table 23 - Peak Flows – Horokiri Hydraulic Model Hydrology

Catchment Pre-Construction Situation Post-Construction Situation

10-Year Storm(Q10)

100-Year Storm Including the

Impacts of Climate Change (Q100cc)

10-Year Storm (Q10)


Impacts of Climate Change

(Q100cc)

M11Horo1 18.7 31.5 18.7 31.5

M11Horo2 1.1 1.9 1.1 2.0

M11Horo3 1.8 3.4 1.9 3.4

M11Horo4 2.0 3.8 2.1 3.8

M11Horo6 2.2 4.1 2.2 4.1

M11Horo8 5.2 9.9 5.3 10.0


Catchment Pre-Construction Situation Post-Construction Situation

10-Year Storm(Q10)


Impacts of Climate Change (Q100cc)

10-Year Storm (Q10)


Impacts of Climate Change

(Q100cc)

M11Horo9 5.1 9.4 5.2 9.5

M11Horo10 4.3 7.4 4.3 7.4

M11Horo11 2.6 4.4 2.6 4.4

M11Horo12 12.3 22.2 12.4 22.3

M11Horo13 1.2 2.0 1.2 2.1

M11Horo15 1.0 1.7 1.0 1.7

M11Horo18 2.0 3.3 2.0 3.4

M11Horo21 3.7 6.2 3.7 6.2

M11Horo26 7.9 13.1 7.9 13.1

Total Inflows 71.1 124.2 71.5 124.7


Figure 68 - Horokiri Stream Hydraulic Model Catchments


E.4.3.1 Calibration

The hydrological calibration of catchment characteristics is recorded provided in Appendix 14.C. This analysis records the calibration and verification of flows at the Greater Wellington Regional Council (GWRC) flow gauge at the Snodgrass property on Paekakariki Hill Road.

During construction of the hydraulic model the compounding effect of the target rainfall events being applied to the 15 sub catchments was found to be over predicting the flows when compared to the calibrated hydrological model predictions at the gauging station. The return period of the rainfall used to generate the inflow hydrographs in the hydraulic model was scaled back until a close match was achieved between the flows in the hydraulic model and the flows predicted by the calibrated hydrological model of the catchment for the design rainfall event.

The hydraulic model indicated that a 2 year rainfall over the 15 Horokiri sub catchments results in flows that are a close match with the 10 year flows predicted by the hydrological model at the gauging station. Similarly a 10 year rainfall over the 15 Horokiri sub catchments results in a close match of flows with those predicted by the calibrated hydrological model for the 100 year flood including the predicted mid range impacts of climate change. A comparison of the flows in the hydraulic model and hydrological model and those from the frequency analysis of the observed data at the gauging station is shown in Table 24. It should be noted that the gauging station has only a short (5-6 years) record and is therefore of only limited value for calibration of the hydraulic model. The close match with the calibrated hydrological model predictions provides sufficient confidence in the model results for an assessment of effects.

Table 24 - Comparison of the Peak Flows in the Hydraulic and Hydrological Model and the Flows Predicted in the Frequency Analysis of the Snodgrass Gauging Station

ARI (Years) Hydraulic Model

Peak Flow (m3/s)

Hydrological Model Peak

Flow (m3/s)

Flood Frequency Analysis

of Snodgrass gauge Data

2002 - 2010 (m3/s)

10 62 60 55

100 133* 132* 116

*Includes the mid range prediction of the impacts of climate change on rainfall intensities. Climate change is predicted to result in c20% increase in peak flood flows


To assess the impacts on the results of changes in the model variables, a sensitivity analysis was undertaken on two key modelling parameters. These variables were the downstream tidal boundary and the inflow hydrographs.


The mouth of the Horokiri stream is tidally influenced due the flat gradient of the stream channel and the low lying floodplain at this location. The sensitivity analysis was undertaken to quantify the impact of assumptions in sea level conditions during the modelled storm events. The model was run with two different tidal levels: 0m above Mean Sea Level (MSL) to simulate a commonly occurring sea level scenario and 2m above MSL to


simulate an extreme sea level including storm surge and wave setup. These levels were selected following a review of tidal water surface levels from Porirua Harbour.

The sensitivity analysis of the sea level boundary indicated that tidal levels only influenced peak water surface levels within about 500m of the stream mouth. Over the majority of the modelled stream network, tidal boundary conditions in the Pauatahanui Inlet were predicted to have no significant impact on peak water surface levels in the stream channel and on the floodplain and therefore little influence on the assessment of hydraulic effects. With this consideration, a mid range boundary condition of 1m above MSL was selected for hydraulic modelling of the pre and post road construction scenarios.


The hydraulic model’s sensitivity to hydrological inputs was tested by running it with an oversized hydrological event and comparing it to the bridge design event. To create the oversized event inflow hydrographs for the hydraulic model, the 100 year storm rainfall including the mid range prediction of climate change was applied across all sub catchments. This resulted in over double the predicted flows for a 100 year flood at the gauging station.

The results of the oversized event revealed significant increases in flooding extents and peak water surface levels over the majority of the modelled stream network. Upstream of Paekakariki Hill Road peak water surface levels were predicted to increase by up to 500mm, while in the lower catchment, downstream of Paekakariki Hill Road, water surface levels were, in places, found to have increased by greater than 1m.

As the Transmission Gully Highway only crosses the Horokiri Stream upstream of Paekakariki Hill Road, this oversized event provided some confidence in the selection of a minimum of 600mm freeboard, from the TransitBridge Manual, when sizing the three proposed bridge crossings.

E.5 Te Puka and Wainui Stream

The topography traversed by the Te Puka and Wainui Streams is typical of the Kapiti Region. The steep upper catchment drops down onto an undulating dune environment. This change in grade between the hills and the coastal zone, combined with the restrictions as the stream runs through the dunes, has resulted in historical flooding problems for the developed land surrounding the stream. For this reason, and the difficulty of constructing a highway through the steep sided valley, these streams have been classified as critical streams and have been investigated in detail to identify the effects of the Transmission Gully Project.


Figure 69 - Te Puka and Wainui Catchment

As shown in Figure 69, the two main streams drain an area of approximately 8 square kilometres, starting in the eastern hills before passing under State Highway 1 (SH1) and the NMIT Railway Line on the low lying coastal area. The streams converge into the Lower Wainui Stream north of the Paekakariki residential area and follow a gentle gradient to the sea.

Landuse in the local drainage area is a mixture of residential, commercial and agriculture on the coastal dunes and a mixture on pasture, plantation pine and native bush on the hills.


The Main Alignment route runs parallel to the Te Puka stream for 3km, from the top of the catchment until it crosses both the Te Puka and the Wainui streams before reconnecting with SH1. The alignment of the proposed highway is shown in Figure 70.

Te

Puka

Str

eam



Figure 70 - Proposed Transmission Gully Alignment and Designation

In this catchment the construction of the highway is complicated by the steep sides of the Te Puka valley. To construct the highway it is likely that in places the earthworks will encroach on to the existing stream, resulting in a number of stream diversions. The hydraulic model has been used to assist in the design of the diversions and identify changes in the stream hydraulics. The model has also been used to appropriately locate and size the stream crossings to help avoid or reduce impacts on the waterway.

E.5.2 Te Puka and Wainui Stream Model

The reaches of the stream channels that were hydraulically modelled are shown above in Figure 70. Almost the full length of the Te Puka has been modelled from the saddle between the Horokiri and Te Puka valleys down to the coast. Only the lower reaches of the Wainui Stream have been modelled as the new highway encroaches on the stream much lower in its catchment.


While a coupled 1D/2D model was used, the steep sides of the Te Puka valley mean that much of the upper catchment was modelled only in the 1D model of the stream. It was only when the floodplain opens out near the coast that flooding spilled out onto the 2D model.


There are seven major structures on the Te Puka / Wainui Stream including various tributaries that pass through culverts under the State highway and railway line, a weir on the main channel west of the highway and the bridge at the southern entrance to QE2 Park. The dimensions of each structure were surveyed as part of this project (see Figure 71).

Figure 71 - Major Structures on the Te Puka / Wainui Stream

28 cross sections of the stream were picked up in the survey. The cross sections picked up the channel invert and spot heights between the true left bank and true right bank. Where possible a cross section was surveyed immediately upstream of the bridges to allow accurate representation of the channel at these hydraulic constraints in the stream model.

E.5.3 Te Puka and Wainui Catchment Hydrology

For the hydrological inputs into the hydraulic model the Te Puka catchment has been subdivided into 25 sub catchments (see Figure 72). The inflow from each sub catchment was extracted from the hydrological model as a discharge time series for entry into the hydraulic model. Peak flows from the sub catchments in both the pre and post construction scenario are detailed in Table 25.


Table 25 - Peak Flows – Te Puka MikeFlood Hydrology

Catchment Pre- Construction Situation Post- Construction Situation

10- Year Storm

(Q10)

100- Year Storm

Including the Impacts

of Climate Change

(Q100cc)

10- Year Storm

(Q10)

100- Year Storm

Including the Impacts of

Climate Change (Q100cc)

M11Wain1 5.2 11.2 5.2 11.2

M11Wain2 1.5 3.1 1.6 3.2

M11Wain3 1.7 3.3 1.7 3.3

M11Wain4 0.7 1.3 0.7 1.3

M11Wain5 2.2 4.9 2.2 4.9

M11Wain6 0.8 1.6 0.8 1.6

M11Wain7 4.0 8.4 4.0 8.4

M11Wain8 0.7 1.5 0.8 1.5

M11Wain9 0.9 1.9 1.0 1.9

M11Wain10 1.1 2.2 1.1 2.2

M11Wain11 0.7 1.4 0.7 1.4

M11Wain12 1.1 2.2 1.1 2.2

M11Wain13 13.4 28.4 13.4 28.4

M11Wain14 1.0 2.2 1.1 2.2

M11Wain15 0.8 1.8 0.9 1.8

M11Wain16 0.7 1.6 0.7 1.6

M11Wain17 1.3 2.8 1.4 2.9

M11Wain18 1.6 3.3 1.6 3.3

M11Wain19 0.9 1.9 0.9 1.9

M11Wain20 0.8 1.9 0.8 1.9

M11Wain21 0.4 0.9 0.4 0.9

M11Wain22 0.2 0.4 0.2 0.4

M11Wain23 0.8 2.0 0.8 2.1

M11Wain24 0.1 0.3 0.1 0.3

M11Wain25 0.2 0.5 0.2 0.5

Total 42.8 91 43.4 91.3


Figure 72 - Te Puka and Wainui Streams Sub Catchments

Note: The catchment, in the northern residential area of Paekakariki, is drained by a long section of stormwater pipe that has not been included in the model. Given the topography and size of the stormwater system it is not considered that this catchment will contribute significantly to the stream flows.


E.5.3.1 Calibration

Very little calibration information was available for either the Te Puka or the Wainui Streams. As neither stream was gauged the calibration has relied on historical flood records to confirm the sensibility of the results. The flood extents were compared with Kapiti Coast District Councils flood records database which records flood damage to buildings. The model extents have also been confirmed as being in line with the experience of Kapiti Coast District Council Stormwater Asset Managers who have a detailed understanding of the flooding issues in this catchment.

A conservative approach to the modelling of runoff from the stream catchment has been taken. The 100 and 10 year rainfall events were used on each of the sub-catchments. With this assumption it is possible that at the lower end of the model the peak water levels are likely to be overestimating the flooding for the return period event being modelled.


To assess the impacts of changes in the model variables, a sensitivity analysis was undertaken on two key modelling parameters that could impact the results and alter the outcomes of the analysis. These variables were the downstream tidal boundary and the inflow hydrographs.


The lower reaches of the catchment are tidally influenced. The sensitivity analysis was undertaken to quantify the impact of assumptions in sea level conditions during the modelled storm events. The model of the 100 year storm event was run with two different tidal levels: an oscillating sea level to simulate an astronomical tide and the same boundary raised by 1.5m to account for storm surge, wave setup and the predicted impacts of climate change.

The modelling results showed that the sea level conditions had very little impact on the catchment flooding in high rainfall events. The reason for this largely relates to the bridge at the southern entrance to QE2 Park. This bridge is a constraint to high flows that masks the influence of the sea level.


The oversized event inflow hydrographs were created by increasing the 100 year flood event, including the mid range predictions of climate change, by half again. This was used to assess the hydraulic model’s sensitivity to variations in hydrological inputs. A comparison of the 100cc year flood flows and the oversized event is shown in Figure 73. These results show that as the floodplain opens up between the hills and the dunes there is up to 500mm difference in flood levels. Flooding on residential property, the highway and the railway is increased by 100-200mm. This provides a measure of confidence in the appropriateness of the freeboard allowance required in the NZTA Bridge Manual that culverts and bridges must convey the 100 year flows with a maximum water depth of 500mm below the carriageway level.


Figure 73 - Comparison of Peak Water Surface Levels Between a 100-Year Event and an Oversized Event


Appendix 14.F. Culvert Catchment Assessment

Table 26 - Culvert Catchment Characteristics

MainCatchment Sub-catchment

Loss Rate Method - SCS Curve Number

Runoff Method - Clark's Unit Hydrograph Q10CC Q100CC

Area(km²)

Initial Abstraction CN CIA

(%) Tc

(Hrs) RatioStorageCoefficie

nt (R) Wainui Wainui 1 0.1 5 78 0 0.26 0.65 0.48 0.841 1.531

Wainui Wainui 2 0.18 5 74 0 0.2 0.65 0.37 1.579 2.963

Wainui Wainui 3 2.64 5 78 0 0.26 0.65 0.48 22.596 41.211

Wainui Wainui 4 0.21 5 79 0 0.28 0.65 0.52 1.719 3.091

Wainui TePuka 1 3.14 5 79 0 0.21 0.65 0.39 29.405 53.441

Wainui TePuka 2 0.09 5 84 0 0.2 0.65 0.38 0.958 1.661

Wainui TePuka 3 0.09 5 84 0 0.26 0.65 0.47 0.86 1.489

Wainui TePuka 4 0.03 5 84 0 0.24 0.65 0.44 0.295 0.51

Wainui TePuka 5 0.1 5 85 0 0.25 0.65 0.47 0.976 1.675

Wainui TePuka 6 0.02 5 84 0 0.17 0.65 0.31 0.237 0.411

Wainui TePuka 7 0.05 5 84 0 0.23 0.65 0.42 0.501 0.865

Wainui TePuka 8 0.08 5 85 0 0.24 0.65 0.44 0.803 1.377

Wainui TePuka 9 0.08 5 84 0 0.24 0.65 0.45 0.779 1.347

Wainui TePuka 10 0.15 5 84 0 0.23 0.65 0.43 1.488 2.57

Wainui TePuka 11 0.04 5 85 0 0.25 0.65 0.46 0.394 0.678

Wainui TePuka 12 0.07 5 84 0 0.28 0.65 0.51 0.64 1.109

Wainui TePuka 13 0.07 5 85 0 0.16 0.65 0.3 0.856 1.472

Wainui TePuka 14 0.03 5 84 0 0.17 0.65 0.31 0.356 0.617

Wainui TePuka 15 0.02 5 85 0 0.21 0.65 0.39 0.213 0.367

Horokiri Horokiri 1 4.48 5 76 0 0.28 0.65 0.51 34.291 63.793





Horokiri Horokiri 6A 0.02 5 85 0 0.17 0.65 0.31 0.242 0.416

Horokiri Horokiri 6B 0.01 5 84 0 0.17 0.65 0.31 0.119 0.206











Area(km²)


(%) Tc


nt (R) Horokiri Horokiri 13 0.05 5 84 0 0.18 0.65 0.33 0.575 0.998









Horokiri Horokiri 21A 0.11 5 79 0 0.23 0.65 0.42 0.998 1.811


















Ration Ration 1 0.47 5 83 0 0.29 0.65 0.54 4.05 7.198

Ration Ration 2 0.02 5 85 0 0.18 0.65 0.34 0.228 0.398

Ration Ration 3 0.12 5 84 0 0.33 0.65 0.61 0.973 1.725

Ration Ration 4 0.01 5 84 0 0.21 0.65 0.39 0.103 0.181

Ration Ration 5 0.03 5 84 0 0.18 0.65 0.33 0.339 0.598

Ration Ration 6 0.01 5 82 0 0.2 0.65 0.37 0.102 0.183

Ration Ration 7 1.49 5 82 0 0.22 0.65 0.41 14.459 25.762

Ration Ration 8 0.29 5 83 0 0.17 0.65 0.31 3.316 5.889





Area(km²)


(%) Tc


nt (R) Ration Ration 9 0.05 5 84 0 0.27 0.65 0.5 0.446 0.802

Ration Ration 10 1.08 5 83 0 0.5 0.65 0.92 6.78 12.151

Ration Ration 10a 0.02 5 85 0 0.32 0.65 0.59 0.168 0.269

Ration Ration 11 0.08 5 85 0 0.17 0.65 0.31 0.924 1.614

Ration Ration 12 0.02 5 84 0 0.28 0.65 0.52 0.173 0.306

Ration Ration 13 0.13 5 83 0 0.29 0.65 0.53 1.085 1.938

Ration Ration 14 0.05 5 85 0 0.31 0.65 0.57 0.41 0.73

Pauatahanui Pauatahanui 1 0.28 5 79 0 0.31 0.65 0.57 2.013 3.767









Duck Duck 1 0.01 5 78 0 0.17 0.65 0.31 0.093 0.178

Duck Duck 2 0.02 5 74 4 0.17 0.65 0.31 0.174 0.339

Duck Duck 3 0.02 5 78 5 0.17 0.65 0.31 0.19 0.357

Duck Duck 4 0.01 5 82 0 0.17 0.65 0.31 0.102 0.187

Duck Duck 5 0.02 5 82 0 0.17 0.65 0.31 0.204 0.374

Duck Duck 6 0.03 5 82 0 0.17 0.65 0.31 0.305 0.561

Duck Duck 7 0.39 5 82 0 0.35 0.65 0.66 2.656 4.951

Duck Duck 8 0.13 5 84 0 0.27 0.65 0.49 1.087 1.969

Duck Duck 9 0.18 5 84 0 0.28 0.65 0.52 1.458 2.642

Duck Duck 10 0.09 5 85 0 0.25 0.65 0.47 0.787 1.411

Duck Duck 11 1.83 5 84 0 0.29 0.65 0.54 14.475 26.474

Duck Duck 12 0.84 5 84 0 0.19 0.65 0.36 8.258 14.929

Duck Duck 13 0.02 5 85 0 0.22 0.65 0.4 0.185 0.336

Duck Duck 14 0.21 5 85 0 0.27 0.65 0.5 1.76 3.185

Duck Duck 15 0.39 5 85 0 0.24 0.65 0.44 3.473 6.267

Duck Duck 16 0.01 5 85 0 0.19 0.65 0.36 0.098 0.18

Duck Duck 17 0.01 4 84 21 0.17 0.65 0.31 0.113 0.199

Duck Duck 18 5.72 5 84 1 0.63 0.65 1.17 29.096 53.008

Duck Duck 19 0.02 5 70 0 0.18 0.65 0.34 0.145 0.296


Table 27 - Culvert Details

Culvert ID Culvert sub-catchment

Chainage(m)

U/S Invert level (m)

D/S Invert Level (m)

CulvertLength (m) Culvert Diameter (mm) Type of fish

passage required

W1 Wainui 1 1525 16 10 155 1050 Std Design


W3 Wainui 3 2100 19 18 96 Two 3m (W) x 2.5m (H) box culverts

Std Design


BSN 3 Te Puka 1 2750 Refer to Schedule of Bridges

T3 Te Puka 3 3075 84 65 91 1050 None

T4 Te Puka 4 3300 98 80 69 600 New Design

T5 Te Puka 5 3475 115 95 56 1050 None

T6 Te Puka 6 3725 134 124 58 600 None

T7 Te Puka 7 3900 148 117 72 900 None

T8 Te Puka 8 4025 152.5 121 85 1050 None

T9 Te Puka 9 4300 178 140 85 1050 None

T10 Te Puka 10 4475 178 150 93 1200 Std Design

T15 Te Puka 15 4575 205 164 84 600 None

T11 Te Puka 11 4775 220 184 80 600 None

T12 Te Puka 12 4875 220.5 185 65 1050 None

T13 Te Puka 13 5025 236.5 218 58 1050 None

T14 Te Puka 14 5200 276 222 245 900 None

H2 Horokiri 2 5375 276 254 266 1050 Std Design

H3 Horokiri 3 5650 257 251 51 1050 New Design

H4 Horokiri 4 5825 247.5 235 72 1050 New Design

H5 Horokiri 5 5930 244 229 69 750 None

H6A Horokiri 6A 6075 236 225 61 600 None

H6B Horokiri 6B 6150 232 218 54 600 None

H7 Horokiri 7 6275 226 218 84 1350 Std Design

H8 Horokiri 8 6400 223 200 73 600 None

H9 Horokiri 9 6575 217 196 57 900 None

H10 Horokiri 10 6625 215 195 58 600 None

H11 Horokiri 11 6675 206 182 80 750 None

H12 Horokiri 12 6850 203 190 64 900 None

H13 Horokiri 13 7050 182 168 72 900 None

H14 Horokiri 14 7250 174 157 93 600 None



H17 Horokiri 17 8000 144 130 64 900 None




Chainage(m)




passage required

H19 Horokiri 19 8375 120 119.5 51 900 New Design

BSN 4 Horokiri 1 8550 Refer to Schedule of Bridges

H21A Horokiri 21A 8850 109 108.5 50 1200 None

H22 Horokiri 22 9000 108 107.5 45 900 None

H23 Horokiri 23 9150 104 103.5 33 600 None

H24 Horokiri 24 9325 98 95 64 3m (W) x 2.5m (H) box culvert

Std Design


H26 Horokiri 26 9925 79.5 75 52 600 None

H27 Horokiri 27 10175 78 74 74 600 None

H29 Horokiri 29 10550 70.5 68 66 900 None

H30 Horokiri 30 10750 69 64 74 600 None

H31 Horokiri 31 10800 69 64 74 600 None

H32 Horokiri 32 11125 63 59 73 600 None

H33 Horokiri 33 11250 56 54 63 900 None


BSN 9 Horokiri 25 n/a Refer to Schedule of Bridges

H34 Horokiri 34 12025 59.5 59 41 600 None

H35 Horokiri 35 12125 62 59 49 900 None

H36 Horokiri 36 12200 63.5 55 96 900 None

H37 Horokiri 37 12400 69 62 81 750 None

BSN 11 Ration 1 12840 Refer to Schedule of Bridges

R2 Ration 2 13000 92.5 89 33 750 None

R3 Ration 3 13100 92.5 86 89 1050 Std Design

R4 Ration 4 13250 95.5 95 50 600 None

R5 Ration 5 13400 91.5 81 113 600 None

R6 Ration 6 13450 88.5 83 86 600 None



R9 Ration 9 13950 83.5 80 72 750 None

R10 Ration 10 14775 48 44 125 2100 Std Design

R10A Ration 10a 14650 58 54 110 600 None

R11 Ration 11 15075 49.5 39 133 1200 None

R12 Ration 12 15350 55.5 48 126 600 None


R14 Ration 14 15800 53.5 44 153 900 None

C1 Collins 1 16125 58.5 58 88 750 None

Pa1 Pauatahanui 1 16700 28 22 107 1200 None



Chainage(m)




passage required

Pa2 Pauatahanui 2 16875 27.5 23 81 1200 Std Design

Pa3 Pauatahanui 3 17000 29 28.5 55 600 None

Pa4 Pauatahanui 4 17175 18 17 63 600 None

Pa5 Pauatahanui 5 17350 13.5 2 128 600 None

Pa6 Pauatahanui 6 17475 6 4 40 1050 Std Design

Pa6A Pauatahanui 6a 17475 6 4 40 1050 None

BSN 15 Pauatahanui 7 17675 Refer to Schedule of Bridges



D17 Duck 17 19550 99 93 62 600 None

D19 Duck 19 n/a 66 65 45 600 None

D20 Duck 20 n/a 79 66 70 600 None

D21 Duck 21 n/a 89 83 46 600 None

D22 Duck 22 n/a 98.5 84 63 600 None

D23 Duck 23 n/a 86.5 79 91 900 None

D24 Duck 24 n/a 92.5 79 95 750 None

D25 Duck 25 n/a 109.5 100 48 600 None

D26 Duck 26 n/a 102 99 44 600 None

D1 Duck 1 19950 105.5 62 195 600 None

D2 Duck 2 20100 95.5 70 141 600 None

D3 Duck 3 20200 95.5 70 128 600 None

D4 Duck 4 20375 93 66 113 600 None

D5 Duck 5 20525 90.5 81 74 600 None

D6 Duck 6 20600 87.5 57 154 600 None

D7 Duck 7 20650 88 62 164 1600 Std Design

D8 Duck 8 21000 94.5 76 119 1050 New Design

D9 Duck 9 21225 95.5 82 167 1200 New Design

D10 Duck 10 21425 107.5 91 109 1050 None

BSN 29 Duck 18 n/a Refer to Schedule of Bridges

BSN 17 n/a 21600 Refer to Schedule of Bridges

BSN 18 n/a 21950 Refer to Schedule of Bridges

D13 Duck 13 22450 141 135 62 600 None

D14 Duck 14 22700 142.5 140 76 1350 Std Design

BSN 19 Duck 15 22850

D16 Duck 16 23050 172 170 49 600 None

DM1* n/a n/a 79.3 76.6 10 Replace as existing Std Design





Chainage(m)




passage required






BSN 20 Kenepuru 1 23650 Refer to Schedule of Bridges

K2 Kenepuru 2 24475 151 146 39 600 None

K3 Kenepuru 3 24625 146.5 145.5 82 600 None

K4 Kenepuru 4 24700 141.5 122 53 600 None

K5 Kenepuru 5 24850 133.5 121 72 900 None

K6 Kenepuru 6 24875 135 112 67 600 None

K7 Kenepuru 7 25100 123.5 109 83 975 None

K8 Kenepuru 8 25200 116 115 49 600 None

K9 Kenepuru 9 25325 115 105 54 1200 New Design

BSN 21 Kenepuru 10 25825 Refer to Schedule of Bridges

BSN 22 Porirua 1 26050 Refer to Schedule of Bridges

Po2 Porirua 2 26200 45.5 36.5 73 600 None

Po3 Porirua 3 26325 54 44 84 825 None

Po4 Porirua 4 26425 58 44 115 900 None

Po5 Porirua 5 26775 45.5 39.5 149 1200 None

Po6 Porirua 6 27000 10.5 9.1 140 975 None

* Replacing existing culverts on grade to allow fish passage, as detailed in Technical Report 11


Table 28 – Temporary Access Culverts Requirements

Catchment Area(ha)

Rainfall Ccoefficient

Intensity (mm/hr)

Tc (hours)

Q2Peak

FishPassage

Required?

Final Culvert

Size(mm)

Or Box Culvert

TC1 317 88 0.35 31 0.58 9.4 Y 3060 3000*1900

TC2 6 86 0.35 41 0.33 0.2 600

TC3 8 86 0.35 45 0.27 0.3 600

TC4 10 86 0.35 44 0.28 0.4 Alternative 750

TC5 3 86 0.35 49 0.23 0.1 600

TC6 220 88 0.35 31 0.57 6.7 Y 2550

TC7 219 88 0.35 31 0.57 6.6 Y 2550

TC8 8 86 0.35 47 0.25 0.4 750

TC9 195 88 0.35 32 0.55 6.0 Y 2300

TC10 37 88 0.35 43 0.31 1.5 Y 1500

TC11 85 88 0.35 42 0.32 3.5 Y 1950

TC12 15 87 0.35 43 0.30 0.6 900

TC13 7 86 0.35 46 0.26 0.3 Y 900

TC14 44 87 0.35 41 0.34 1.7 Y 1500

TC15 64 87 0.35 31 0.55 1.9 Y 1650

TC16 17 86 0.35 44 0.28 0.7 Y 1200

TC17 114 87 0.35 31 0.55 3.5 Y 1950

TC18 30 88 0.35 42 0.32 1.3 1050

TC19 155 87 0.35 30 0.60 4.5 Y 2300

TC20 6 86 0.35 51 0.22 0.3 600

TC21 214 87 0.35 30 0.60 6.2 Y 2300

TC22 219 87 0.35 30 0.60 6.4 Y 2300

TC23 225 87 0.35 30 0.60 6.5 Y 2300

TC24 226 87 0.35 30 0.60 6.6 Y 2300

TC25 241 87 0.35 25 0.82 5.9 Y 2300

TC26 2 87 0.35 50 0.23 0.1 600

TC27 3 87 0.35 50 0.23 0.2 600

TC28 314 87 0.35 24 0.93 7.2 Y 2550

TC29 453 87 0.35 23 0.97 10.2 Y 3060 3000*1900

TC30 5 87 0.35 47 0.26 0.2 600

TC31 105 88 0.35 34 0.48 3.4 Y 1950

TC32 640 87 0.35 20 1.25 12.5 Y 3060 3000*2200

TC33 4 86 0.35 44 0.28 0.2 600


Catchment Area(ha)

Rainfall Ccoefficient

Intensity (mm/hr)

Tc (hours)

Q2Peak

FishPassage

Required?

Final Culvert

Size(mm)

Or Box Culvert

TC34 2 85 0.35 44 0.28 0.1 600

TC35 1059 87 0.35 18 1.57 18.4 Y 3000*2800

TC36 22 85 0.35 39 0.35 0.8 Y 1200

TC37 3 84 0.35 40 0.32 0.1 Y 750

TC38 1 84 0.35 47 0.24 0.0 Y 600

TC39 50 85 0.35 33 0.46 1.6 Y 1500

TC40 51 85 0.35 33 0.46 1.7 Y 1500

TC41 113 84 0.35 28 0.63 3.1 Y 1800

TC42 7 83 0.35 39 0.33 0.3 600

TC43 3 83 0.35 39 0.33 0.1 600

TC44 13 83 0.35 38 0.34 0.5 Y 1050

TC45 3 82 0.35 41 0.29 0.1 600

TC46 3 82 0.35 41 0.30 0.1 600

TC47 1 82 0.35 44 0.26 0.1 600

TC48 19 82 0.35 36 0.38 0.7 900

TC49 10 81 0.35 39 0.32 0.4 750

TC50 576 78 0.35 21 0.92 11.9 Y 3060 3000*2100

TC51 0 76 0.35 47 0.20 0.0 600

TC52 2 76 0.35 40 0.27 0.1 600

TC53 1 76 0.35 44 0.22 0.0 600

TC54 1 76 0.35 45 0.22 0.0 600

TC55 1 76 0.35 45 0.21 0.0 600

TC56 1 76 0.35 44 0.22 0.0 600

TC57 3 75 0.35 40 0.26 0.1 Y 750

TC58 40 75 0.35 34 0.35 1.3 Y 1350

TC59 1 75 0.35 43 0.23 0.1 600

TC60 4 75 0.35 39 0.28 0.2 600

TC61 11 75 0.35 35 0.34 0.4 750





Area(km²)


(%) Tc


nt (R) Duck Duck 20 0.03 5 72 0 0.22 0.65 0.4 0.206 0.415

Duck Duck 21 0.01 5 72 0 0.23 0.65 0.43 0.067 0.134

Duck Duck 22 0.02 4 74 29 0.2 0.65 0.36 0.181 0.333

Duck Duck 23 0.09 5 83 1 0.24 0.65 0.44 0.771 1.41

Duck Duck 24 0.05 5 84 0 0.23 0.65 0.44 0.428 0.79

Duck Duck 25 0.03 5 85 0 0.23 0.65 0.43 0.265 0.48

Duck Duck 26 0.03 5 84 0 0.21 0.65 0.4 0.27 0.494

Collins Collins 1 0.04 5 84 0 0.26 0.65 0.48 0.356 0.638

Kenepuru Kenepuru 1 1.49 5 94 0 0.38 0.65 0.71 12.038 20.391










Porirua Porirua 1 0.39 5 89 2 0.17 0.65 0.31 4.44 7.584

Porirua Porirua 2 0.02 2 91 54 0.17 0.65 0.32 0.248 0.402

Porirua Porirua 3 0.05 4 91 25 0.18 0.65 0.34 0.56 0.963

Porirua Porirua 4 0.1 5 92 9 0.29 0.65 0.54 0.906 1.509

Porirua Porirua 5 0.24 5 84 0 0.39 0.65 0.73 1.536 2.784

Porirua Porirua 6 0.13 5 78 0 0.29 0.65 0.54 0.824 1.626

Porirua Porirua 7 0.83 4 76 10 0.4 0.65 0.74 4.633 8.703


Appendix 14.G. Culvert Catchments

P.M

GR

RE

VIE

WN

oD

ATE

DE

SIG

NR

EV'

DP.

DIR

APP

'DAM

EN

DM

EN

T

The

conc

epts

and

info

rmat

ion

cont

aine

din

this

doc

umen

t are

the

copy

right

of

Sinc

lair

Kni

ght M

erz

Ltd.

Use

or

copy

ing

of th

e do

cum

ent i

n w

hole

or i

npa

rt w

ithou

t the

writ

ten

perm

issi

on o

fSi

ncla

ir K

nigh

t Mer

z Lt

d. c

onst

itute

san

infri

ngem

ent o

f cop

yrig

ht.

DE

SIG

NED

DR

AW

N

PRO

JEC

T

CLI

EN

T

DA

TE

DE

SIG

N R

EVI

EW

RE

VIE

WE

DPR

OJE

CT

MA

NAG

ER

PRO

JEC

T D

IRE

CTO

RAP

PR

OV

ED

SCAL

E

TITL

E

SKM

PR

OJE

CT

No

DR

AW

ING

No

AMD

T

CH

EC

KD

RA

FTIN

G

FILENAME:PLOT DATE:

CO

PYR

IGH

T

FEDCBA

A3

87

65

43

21

FD EB CA

12

34

56

78

Leve

l 12,

May

fair

Hou

seP5

4 Th

e Te

rrace

PPO

Box

10-

283,

Wel

lingt

onPN

EW

ZEA

LAN

DPT

el +

64 4

473

426

5PF

ax +

64 4

473

336

9

WD

1

BSN

3

TD2

TD3

! (T5! (T4

! (T3

! (W1

! (W2

! (W3

! (W4

Wai

nui 3

Wai

nui 4

Wai

nui 2

Wai

nui 1

TePu

ka 5

TePu

ka 2

TePu

ka 3

TePu

ka 4

TePu

ka 6

[

CU

LVE

RT

CAT

CH

ME

NTS

SH

EE

T 1

NEW

ZE

ALA

ND

TR

ANSP

OR

T AG

EN

CY

TRA

NS

MIS

SIO

N G

ULL

Y P

RO

JEC

TTE

CH

NIC

AL

RE

PO

RT

14

1:8,

000

AE

0377

8

Leve

l 3, 8

6 C

usto

mho

use

Qua

yS

JB CM

M

JULY

201

1

Leve

l 3, 8

6 cu

stom

hous

e Q

uay

Wel

lingt

on 6

011

PO B

ox 1

0-28

3, W

ellin

gton

614

3NE

W Z

EALA

ND

Tel +

64 4

473

426

5Fa

x +6

4 4

473

3369

13

26

9

4

78

5

010

020

030

040

050

0 m

Brid

ges

( BS

N1

etc)

( **D

1 et

c)

( **1

etc

)

Stre

am D

iver

sion

s

Con

tour

s 2m

Prop

osed

Cul

vert

s

no fi

sh p

assa

ge re

quire

d

fish

pass

age

requ

ired

alte

rnat

ive

fish

pass

age

requ

ired

Roa

d C

atch

men

ts

I:\AENVW\Projects\AE03778\Deliverables\Final Collated Report WS4\Delivered June 2011\Appendix G\MXD's

TG A

LIG

NM

EN

T AS

AT

09 S

EP

TEM

BE

R 2

010

A

P.M

GR

RE

VIE

WN

oD

ATE

DE

SIG

NR

EV'

DP.

DIR

APP

'DAM

EN

DM

EN

T

The

conc

epts

and

info

rmat

ion

cont

aine

din

this

doc

umen

t are

the

copy

right

of

Sinc

lair

Kni

ght M

erz

Ltd.

Use

or

copy

ing

of th

e do

cum

ent i

n w

hole

or i

npa

rt w

ithou

t the

writ

ten

perm

issi

on o

fSi

ncla

ir K

nigh

t Mer

z Lt

d. c

onst

itute

san

infri

ngem

ent o

f cop

yrig

ht.

DE

SIG

NED

DR

AW

N

PRO

JEC

T

CLI

EN

T

DA

TE

DE

SIG

N R

EVI

EW

RE

VIE

WE

DPR

OJE

CT

MA

NAG

ER

PRO

JEC

T D

IRE

CTO

RAP

PR

OV

ED

SCAL

E

TITL

E

SKM

PR

OJE

CT

No

DR

AW

ING

No

AMD

T

CH

EC

KD

RA

FTIN

G

FILENAME:PLOT DATE:

CO

PYR

IGH

T

FEDCBA

A3

87

65

43

21

FD EB CA

12

34

56

78

Leve

l 12,

May

fair

Hou

seP5

4 Th

e Te

rrace

PPO

Box

10-

283,

Wel

lingt

onPN

EW

ZEA

LAN

DPT

el +

64 4

473

426

5PF

ax +

64 4

473

336

9

Leve

l 12,

May

fair

Hou

se54

The

Ter

race

PO B

ox 1

0-28

3, W

ellin

gton

NEW

ZEA

LAN

DTe

l +64

4 4

73 4

265

Fax

+64

4 47

3 33

69

HD

2

HD

1

TD4

! (H2! (T1

4

! (T10

! (T15

! (T12

! (T8! (T9

! (T7! (T6

! (H4

! (T11

! (H3

! (T13

! (H8! (H5

! (H6A

! (H6B

! (H7

TePu

ka 1

Wai

nui 3

Hor

okiri

7

TePu

ka 1

0

Hor

okiri

4H

orok

iri 3

Hor

okiri

2

TePu

ka 9

TePu

ka 8

TePu

ka 5

TePu

ka 1

2

TePu

ka 1

3

TePu

ka 7

TePu

ka 1

1

Hor

okiri

5

TePu

ka 1

4

Hor

okiri

9

TePu

ka 6

TePu

ka 1

5

Hor

okiri

6A

Hor

okiri

8H

orok

iri 6

B

Hor

okiri

10

PLA

NS

ET

1C

ULV

ER

T C

ATC

HM

EN

TSS

HE

ET

2

NEW

ZE

ALA

ND

TR

ANSP

OR

T AG

EN

CY

TRAN

SMIS

SIO

N G

ULL

Y PR

OJE

CT

TEC

HN

ICAL

REP

OR

T 14

1:8,

000

AE03

778

Leve

l 3, 8

6 C

usto

mho

use

Qua

ySJ

B

CM

M

JULY

201

11

32

6

9

47

8

5

[

010

020

030

040

050

0 m

Brid

ges

( BS

N1

etc)

( **D

1 et

c)

( **1

etc

)

Stre

am D

iver

sion

s

Con

tour

s 2m

Prop

osed

Cul

vert

s

no fi

sh p

assa

ge re

quire

d

fish

pass

age

requ

ired

alte

rnat

ive

fish

pass

age

requ

ired

Roa

d C

atch

men

ts


TG A

LIG

NM

EN

T AS

AT

09 S

EP

TEM

BE

R 2

010

A

P.M

GR

RE

VIE

WN

oD

ATE

DE

SIG

NR

EV'

DP.

DIR

APP

'DAM

EN

DM

EN

T

The

conc

epts

and

info

rmat

ion

cont

aine

din

this

doc

umen

t are

the

copy

right

of

Sinc

lair

Kni

ght M

erz

Ltd.

Use

or

copy

ing

of th

e do

cum

ent i

n w

hole

or i

npa

rt w

ithou

t the

writ

ten

perm

issi

on o

fSi

ncla

ir K

nigh

t Mer

z Lt

d. c

onst

itute

san

infri

ngem

ent o

f cop

yrig

ht.

DE

SIG

NED

DR

AW

N

PRO

JEC

T

CLI

EN

T

DA

TE

DE

SIG

N R

EVI

EW

RE

VIE

WE

DPR

OJE

CT

MA

NAG

ER

PRO

JEC

T D

IRE

CTO

RAP

PR

OV

ED

SCAL

E

TITL

E

SKM

PR

OJE

CT

No

DR

AW

ING

No

AMD

T

CH

EC

KD

RA

FTIN

G

FILENAME:PLOT DATE:

CO

PYR

IGH

T

FEDCBA

A3

87

65

43

21

FD EB CA

12

34

56

78

Leve

l 12,

May

fair

Hou

seP5

4 Th

e Te

rrace

PPO

Box

10-

283,

Wel

lingt

onPN

EW

ZEA

LAN

DPT

el +

64 4

473

426

5PF

ax +

64 4

473

336

9

Leve

l 12,

May

fair

Hou

se54

The

Ter

race

PO B

ox 1

0-28

3, W

ellin

gton

NEW

ZEA

LAN

DTe

l +64

4 4

73 4

265

Fax

+64

4 47

3 33

69

HD

4H

D5

HD

3B

SN4

! (H24

! (H11

! (H15

! (H14

! (H10

! (H12

! (H17

! (H16

! (H13

! (H18

! (H19

! (H21

A

! (H23

! (H22

! (H9

Hor

okiri

1H

orok

iri 2

5

Hor

okiri

24

Hor

okiri

21

Hor

okiri

15

Hor

okiri

16

Hor

okiri

21A

Hor

okiri

18

Hor

okiri

19

Hor

okiri

17

Hor

okiri

22

Hor

okiri

12

Hor

okiri

13

Hor

okiri

20

Hor

okiri

11

Hor

okiri

14

Hor

okiri

23

Hor

okiri

10

Hor

okiri

9

PLA

NS

ET

1C

ULV

ER

T C

ATC

HM

EN

TSS

HE

ET

3

NEW

ZE

ALA

ND

TR

ANSP

OR

T AG

EN

CY

TRAN

SMIS

SIO

N G

ULL

Y PR

OJE

CT

TEC

HN

ICAL

REP

OR

T 14

1:8,

000

AE03

778

Leve

l 3, 8

6 C

usto

mho

use

Qua

ySJ

B

CM

M

JULY

201

13

12

6

9

4

78

5


[

010

020

030

040

050

0 m

Brid

ges

( BS

N1

etc)

( **D

1 et

c)

( **1

etc

)

Stre

am D

iver

sion

s

Con

tour

s 2m

Prop

osed

Cul

vert

s

no fi

sh p

assa

ge re

quire

d

fish

pass

age

requ

ired

alte

rnat

ive

fish

pass

age

requ

ired

Roa

d C

atch

men

ts

TG A

LIG

NM

EN

T AS

AT

09 S

EP

TEM

BE

R 2

010

A

P.M

GR

RE

VIE

WN

oD

ATE

DE

SIG

NR

EV'

DP.

DIR

APP

'DAM

EN

DM

EN

T

The

conc

epts

and

info

rmat

ion

cont

aine

din

this

doc

umen

t are

the

copy

right

of

Sinc

lair

Kni

ght M

erz

Ltd.

Use

or

copy

ing

of th

e do

cum

ent i

n w

hole

or i

npa

rt w

ithou

t the

writ

ten

perm

issi

on o

fSi

ncla

ir K

nigh

t Mer

z Lt

d. c

onst

itute

san

infri

ngem

ent o

f cop

yrig

ht.

DE

SIG

NED

DR

AW

N

PRO

JEC

T

CLI

EN

T

DA

TE

DE

SIG

N R

EVI

EW

RE

VIE

WE

DPR

OJE

CT

MA

NAG

ER

PRO

JEC

T D

IRE

CTO

RAP

PR

OV

ED

SCAL

E

TITL

E

SKM

PR

OJE

CT

No

DR

AW

ING

No

AMD

T

CH

EC

KD

RA

FTIN

G

FILENAME:PLOT DATE:

CO

PYR

IGH

T

FEDCBA

A3

87

65

43

21

FD EB CA

12

34

56

78

Leve

l 12,

May

fair

Hou

seP5

4 Th

e Te

rrace

PPO

Box

10-

283,

Wel

lingt

onPN

EW

ZEA

LAN

DPT

el +

64 4

473

426

5PF

ax +

64 4

473

336

9

Leve

l 12,

May

fair

Hou

se54

The

Ter

race

PO B

ox 1

0-28

3, W

ellin

gton

NEW

ZEA

LAN

DTe

l +64

4 4

73 4

265

Fax

+64

4 47

3 33

69

BSN

8

BSN

9

BSN

6

! (H36

! (H32

! (H37

! (H30

! (H29

! (H34

! (H27

! (H26

! (H33

! (H31

! (H35

Hor

okiri

25

Rat

ion

1

Hor

okiri

36

Hor

okiri

21

Hor

okiri

28

Hor

okiri

33

Hor

okiri

27

Hor

okiri

26

Hor

okiri

29

Hor

okiri

31

Hor

okiri

35

Hor

okiri

37

Hor

okiri

38

Hor

okiri

34

Hor

okiri

32

Hor

okiri

30

Hor

okiri

24

NEW

ZE

ALA

ND

TR

ANSP

OR

T AU

THO

RIT

YTR

ANSM

ISSI

ON

GU

LLY

PRO

JEC

TTE

CH

NIC

AL R

EPO

RT

14

1:8,

000

AE03

778

Leve

l 3, 8

6 C

usto

mho

use

Qua

ySJ

B

CM

M

JULY

201

1

PLA

NS

ET

1C

ULV

ER

T C

ATC

HM

EN

TSS

HE

ET

41

32

6

9

4

78

5


[

010

020

030

040

050

0 m

Brid

ges

( BS

N1

etc)

( **D

1 et

c)

( **1

etc

)

Stre

am D

iver

sion

s

Con

tour

s 2m

Prop

osed

Cul

vert

s

no fi

sh p

assa

ge re

quire

d

fish

pass

age

requ

ired

alte

rnat

ive

fish

pass

age

requ

ired

Roa

d C

atch

men

ts

TG A

LIG

NM

EN

T AS

AT

09 S

EP

TEM

BE

R 2

010

A

P.M

GR

RE

VIE

WN

oD

ATE

DE

SIG

NR

EV'

DP.

DIR

APP

'DAM

EN

DM

EN

T

The

conc

epts

and

info

rmat

ion

cont

aine

din

this

doc

umen

t are

the

copy

right

of

Sinc

lair

Kni

ght M

erz

Ltd.

Use

or

copy

ing

of th

e do

cum

ent i

n w

hole

or i

npa

rt w

ithou

t the

writ

ten

perm

issi

on o

fSi

ncla

ir K

nigh

t Mer

z Lt

d. c

onst

itute

san

infri

ngem

ent o

f cop

yrig

ht.

DE

SIG

NED

DR

AW

N

PRO

JEC

T

CLI

EN

T

DA

TE

DE

SIG

N R

EVI

EW

RE

VIE

WE

DPR

OJE

CT

MA

NAG

ER

PRO

JEC

T D

IRE

CTO

RAP

PR

OV

ED

SCAL

E

TITL

E

SKM

PR

OJE

CT

No

DR

AW

ING

No

AMD

T

CH

EC

KD

RA

FTIN

G

FILENAME:PLOT DATE:

CO

PYR

IGH

T

FEDCBA

A3

87

65

43

21

FD EB CA

12

34

56

78

Leve

l 12,

May

fair

Hou

seP5

4 Th

e Te

rrace

PPO

Box

10-

283,

Wel

lingt

onPN

EW

ZEA

LAN

DPT

el +

64 4

473

426

5PF

ax +

64 4

473

336

9

Leve

l 12,

May

fair

Hou

se54

The

Ter

race

PO B

ox 1

0-28

3, W

ellin

gton

NEW

ZEA

LAN

DTe

l +64

4 4

73 4

265

Fax

+64

4 47

3 33

69

RD

1

RD

2

RD

3

BSN

11

! (R10

! (R7! (R9

! (R5! (R8

! (R11

! (R12

! (R10

a

! (R13

! (R3! (R2

! (R4! (R6

Rat

ion

10

Paua

taha

nui 7

Rat

ion

7

Rat

ion

1R

atio

n 8

Rat

ion

3

Rat

ion

13R

atio

n 11

Rat

ion

9

Rat

ion

5

Rat

ion

2

Rat

ion

12R

atio

n 10

a

Rat

ion

6R

atio

n 4

Hor

okiri

38

Rat

ion

14

Rat

ion

14

NEW

ZE

ALA

ND

TR

ANSP

OR

T AG

EN

CY

TRAN

SMIS

SIO

N G

ULL

Y PR

OJE

CT

TEC

HN

ICAL

REP

OR

T 14

1:8,

000

AE03

778

Leve

l 3, 8

6 C

usto

mho

use

Qua

ySJ

B

CBL

JULY

201

1

PLA

NS

ET

1C

ULV

ER

T C

ATC

HM

EN

TSS

HE

ET

51

32

6

9

4

78

5

[

010

020

030

040

050

0 m

Brid

ges

( BS

N1

etc)

( **D

1 et

c)

( **1

etc

)

Stre

am D

iver

sion

s

Con

tour

s 2m

Prop

osed

Cul

vert

s

no fi

sh p

assa

ge re

quire

d

fish

pass

age

requ

ired

alte

rnat

ive

fish

pass

age

requ

ired

Roa

d C

atch

men

ts


TG A

LIG

NM

EN

T AS

AT

09 S

EP

TEM

BE

R 2

010

A

P.M

GR

RE

VIE

WN

oD

ATE

DE

SIG

NR

EV'

DP.

DIR

APP

'DAM

EN

DM

EN

T

The

conc

epts

and

info

rmat

ion

cont

aine

din

this

doc

umen

t are

the

copy

right

of

Sinc

lair

Kni

ght M

erz

Ltd.

Use

or

copy

ing

of th

e do

cum

ent i

n w

hole

or i

npa

rt w

ithou

t the

writ

ten

perm

issi

on o

fSi

ncla

ir K

nigh

t Mer

z Lt

d. c

onst

itute

san

infri

ngem

ent o

f cop

yrig

ht.

DE

SIG

NED

DR

AW

N

PRO

JEC

T

CLI

EN

T

DA

TE

DE

SIG

N R

EVI

EW

RE

VIE

WE

DPR

OJE

CT

MA

NAG

ER

PRO

JEC

T D

IRE

CTO

RAP

PR

OV

ED

SCAL

E

TITL

E

SKM

PR

OJE

CT

No

DR

AW

ING

No

AMD

T

CH

EC

KD

RA

FTIN

G

FILENAME:PLOT DATE:

CO

PYR

IGH

T

FEDCBA

A3

87

65

43

21

FD EB CA

12

34

56

78

Leve

l 12,

May

fair

Hou

seP5

4 Th

e Te

rrace

PPO

Box

10-

283,

Wel

lingt

onPN

EW

ZEA

LAN

DPT

el +

64 4

473

426

5PF

ax +

64 4

473

336

9

Leve

l 12,

May

fair

Hou

se54

The

Ter

race

PO B

ox 1

0-28

3, W

ellin

gton

NEW

ZEA

LAN

DTe

l +64

4 4

73 4

265

Fax

+64

4 47

3 33

69

PAD

3

PAD

1

PAD

4B

SN15

! (R14

! (Pa5

! (Pa1

! (R13

! (Pa2

! (Pa9

! (C1

! (Pa8

! (Pa4

! (Pa6a

! (Pa3

! (Pa6

PAD

2

Paua

taha

nui 7

Paua

taha

nui 1

Paua

taha

nui 2

Paua

taha

nui 6

Paua

taha

nui 8

Rat

ion

13

Col

lins

1R

atio

n 14

Paua

taha

nui 5

Paua

taha

nui 3

Paua

taha

nui 4

Paua

taha

nui 9

NEW

ZE

ALA

ND

TR

ANSP

OR

T AG

EN

CY

TRAN

SMIS

SIO

N G

ULL

Y PR

OJE

CT

TEC

HN

ICAL

REP

OR

T 14

1:8,

000

AE03

778

Leve

l 3, 8

6 C

usto

mho

use

Qua

ySJ

B

CM

M

JULY

201

1

PLA

NS

ET

1C

ULV

ER

T C

ATC

HM

EN

TSS

HE

ET

61

32

6

9

47

8

5


[

010

020

030

040

050

0 m

Brid

ges

( BS

N1

etc)

( **D

1 et

c)

( **1

etc

)

Stre

am D

iver

sion

s

Con

tour

s 2m

Prop

osed

Cul

vert

s

no fi

sh p

assa

ge re

quire

d

fish

pass

age

requ

ired

alte

rnat

ive

fish

pass

age

requ

ired

Roa

d C

atch

men

ts

TG A

LIG

NM

EN

T AS

AT

09 S

EP

TEM

BE

R 2

010

A

P.M

GR

RE

VIE

WN

oD

ATE

DE

SIG

NR

EV'

DP.

DIR

APP

'DAM

EN

DM

EN

T

The

conc

epts

and

info

rmat

ion

cont

aine

din

this

doc

umen

t are

the

copy

right

of

Sinc

lair

Kni

ght M

erz

Ltd.

Use

or

copy

ing

of th

e do

cum

ent i

n w

hole

or i

npa

rt w

ithou

t the

writ

ten

perm

issi

on o

fSi

ncla

ir K

nigh

t Mer

z Lt

d. c

onst

itute

san

infri

ngem

ent o

f cop

yrig

ht.

DE

SIG

NED

DR

AW

N

PRO

JEC

T

CLI

EN

T

DA

TE

DE

SIG

N R

EVI

EW

RE

VIE

WE

DPR

OJE

CT

MA

NAG

ER

PRO

JEC

T D

IRE

CTO

RAP

PR

OV

ED

SCAL

E

TITL

E

SKM

PR

OJE

CT

No

DR

AW

ING

No

AMD

T

CH

EC

KD

RA

FTIN

G

FILENAME:PLOT DATE:

CO

PYR

IGH

T

FEDCBA

A3

87

65

43

21

FD EB CA

12

34

56

78

Leve

l 12,

May

fair

Hou

seP5

4 Th

e Te

rrace

PPO

Box

10-

283,

Wel

lingt

onPN

EW

ZEA

LAN

DPT

el +

64 4

473

426

5PF

ax +

64 4

473

336

9

Leve

l 12,

May

fair

Hous

e54

The

Ter

race

PO B

ox 1

0-28

3, W

ellin

gton

NEW

ZEA

LAN

DTe

l +64

4 4

73 4

265

Fax

+64

4 47

3 33

69

BSN

29

! (D1

! (D2

! (D9

! (D6

! (D24

! (D10

! (D8

! (D7

! (D5

! (D20

! (D22

! (D17

! (D25

! (D4

! (D19

! (D26

! (D21

! (D3

! (D23

Duc

k 18

Paua

taha

nui 7

Duc

k 7

Duc

k 23

Duc

k 8

Duc

k 9

Duc

k 24D

uck

26

Duc

k 25

Duc

k 6

Duc

k 10

Duc

k 3D

uck

20 Duc

k 2

Duc

k 22 D

uck

19

Duc

k 21

Duc

k 11

Duc

k 5

Duc

k 1

Paua

taha

nui 8

Paua

taha

nui 9

Duc

k 4

Duc

k 17

NEW

ZE

ALA

ND

TR

AN

SPO

RT

AG

ENC

YTR

ANSM

ISSI

ON

GU

LLY

PRO

JEC

TTE

CH

NIC

AL R

EPO

RT

14

1:8,

000

AE03

778

Leve

l 3, 8

6 C

usto

mho

use

Qua

ySJ

B

CM

M

JULY

201

1

PLA

NSE

T 1

CU

LVER

T C

ATC

HM

ENTS

SHEE

T 7

13

26

9

4

78

5

[

010

020

030

040

050

0 m

Brid

ges

( BSN

1 et

c)

( **D

1 et

c)

( **1

etc

)

Stre

am D

iver

sion

s

Con

tour

s 2m

Prop

osed

Cul

vert

s

no fi

sh p

assa

ge re

quire

d

fish

pass

age

requ

ired

alte

rnat

ive

fish

pass

age

requ

ired

Roa

d C

atch

men

ts


TG A

LIG

NM

ENT

AS

AT 0

9 SE

PTE

MBE

R 2

010

A

P.M

GR

RE

VIE

WN

oD

ATE

DE

SIG

NR

EV'

DP.

DIR

APP

'DAM

EN

DM

EN

T

The

conc

epts

and

info

rmat

ion

cont

aine

din

this

doc

umen

t are

the

copy

right

of

Sinc

lair

Kni

ght M

erz

Ltd.

Use

or

copy

ing

of th

e do

cum

ent i

n w

hole

or i

npa

rt w

ithou

t the

writ

ten

perm

issi

on o

fSi

ncla

ir K

nigh

t Mer

z Lt

d. c

onst

itute

san

infri

ngem

ent o

f cop

yrig

ht.

DE

SIG

NED

DR

AW

N

PRO

JEC

T

CLI

EN

T

DA

TE

DE

SIG

N R

EVI

EW

RE

VIE

WE

DPR

OJE

CT

MA

NAG

ER

PRO

JEC

T D

IRE

CTO

RAP

PR

OV

ED

SCAL

E

TITL

E

SKM

PR

OJE

CT

No

DR

AW

ING

No

AMD

T

CH

EC

KD

RA

FTIN

G

FILENAME:PLOT DATE:

CO

PYR

IGH

T

FEDCBA

A3

87

65

43

21

FD EB CA

12

34

56

78

Leve

l 12,

May

fair

Hou

seP5

4 Th

e Te

rrace

PPO

Box

10-

283,

Wel

lingt

onPN

EW

ZEA

LAN

DPT

el +

64 4

473

426

5PF

ax +

64 4

473

336

9

Leve

l 12,

May

fair

Hou

se54

The

Ter

race

PO B

ox 1

0-28

3, W

ellin

gton

NEW

ZEA

LAN

DTe

l +64

4 4

73 4

265

Fax

+64

4 47

3 33

69

BSN

20

BSN

19

BSN

18

BSN

17

DD

1

KD

1

! (K5

! (D14

! (K4 ! (K

2

! (D16

! (D13

! (K3

Ken

epur

u 1

Duc

k 15

Duc

k 12

Duc

k 14

Duc

k 11

Ken

epur

u 5

Ken

epur

u 4

Ken

epur

u 3

Ken

epur

u 2

Duc

k 13

Ken

epur

u 7

Duc

k 16

Ken

epur

u 6

Duc

k 10

NEW

ZE

ALA

ND

TR

ANSP

OR

T AU

THO

RIT

YTR

ANSM

ISSI

ON

GU

LLY

PRO

JEC

TTE

CH

NIC

AL R

EPO

RT

14

1:8,

000

AE03

778

Leve

l 3, 8

6 C

usto

mho

use

Qua

ySJ

B

CM

M

JULY

201

1

PLA

NS

ET

1C

ULV

ER

T C

ATC

HM

EN

TSS

HE

ET

81

32

6

9

4

78

5


TG A

LIG

NM

EN

T AS

AT

09 S

EP

TEM

BE

R 2

010

[

010

020

030

040

050

0 m

Brid

ges

( BS

N1

etc)

( **D

1 et

c)

( **1

etc

)

Stre

am D

iver

sion

s

Con

tour

s 2m

Prop

osed

Cul

vert

s

no fi

sh p

assa

ge re

quire

d

fish

pass

age

requ

ired

alte

rnat

ive

fish

pass

age

requ

ired

Roa

d C

atch

men

ts

A

P.M

GR

RE

VIE

WN

oD

ATE

DE

SIG

NR

EV'

DP.

DIR

APP

'DAM

EN

DM

EN

T

The

conc

epts

and

info

rmat

ion

cont

aine

din

this

doc

umen

t are

the

copy

right

of

Sinc

lair

Kni

ght M

erz

Ltd.

Use

or

copy

ing

of th

e do

cum

ent i

n w

hole

or i

npa

rt w

ithou

t the

writ

ten

perm

issi

on o

fSi

ncla

ir K

nigh

t Mer

z Lt

d. c

onst

itute

san

infri

ngem

ent o

f cop

yrig

ht.

DE

SIG

NED

DR

AW

N

PRO

JEC

T

CLI

EN

T

DA

TE

DE

SIG

N R

EVI

EW

RE

VIE

WE

DPR

OJE

CT

MA

NAG

ER

PRO

JEC

T D

IRE

CTO

RAP

PR

OV

ED

SCAL

E

TITL

E

SKM

PR

OJE

CT

No

DR

AW

ING

No

AMD

T

CH

EC

KD

RA

FTIN

G

FILENAME:PLOT DATE:

CO

PYR

IGH

T

FEDCBA

A3

87

65

43

21

FD EB CA

12

34

56

78

Leve

l 12,

May

fair

Hou

seP5

4 Th

e Te

rrace

PPO

Box

10-

283,

Wel

lingt

onPN

EW

ZEA

LAN

DPT

el +

64 4

473

426

5PF

ax +

64 4

473

336

9

Leve

l 12,

May

fair

Hou

se54

The

Ter

race

PO B

ox 1

0-28

3, W

ellin

gton

NEW

ZEA

LAN

DTe

l +64

4 4

73 4

265

Fax

+64

4 47

3 33

69

BSN

22

PoD

1

BSN

21 KD

2

PoD

2

! (Po4

! (Po2

! (Po6

! (K7

! (Po3

! (Po5

! (K8! (K9

! (K6

Porir

ua 7

Porir

ua 1

Porir

ua 5

Porir

ua 6

Ken

epur

u 9

Porir

ua 4

Ken

epur

u 7

Porir

ua 3

Ken

epur

u 8

Ken

epur

u 10

Porir

ua 2

Ken

epur

u 6

Ken

epur

u 5

NEW

ZE

ALA

ND

TR

ANSP

OR

T AU

THO

RIT

YTR

ANSM

ISSI

ON

GU

LLY

PRO

JEC

TTE

CH

NIC

AL R

EPO

RT

14

1:8,

000

AE03

778

Leve

l 3, 8

6 C

usto

mho

use

Qua

ySJ

B

CM

M

JULY

201

1

PLA

NS

ET

1C

ULV

ER

T C

ATC

HM

EN

TSS

HE

ET

91

32

6

9

4

78

5

[

010

020

030

040

050

0 m

Brid

ges

( BS

N1

etc)

( **D

1 et

c)

( **1

etc

)

Stre

am D

iver

sion

s

Con

tour

s 2m

Prop

osed

Cul

vert

s

no fi

sh p

assa

ge re

quire

d

fish

pass

age

requ

ired

alte

rnat

ive

fish

pass

age

requ

ired

Roa

d C

atch

men

ts


TG A

LIG

NM

EN

T AS

AT

09 S

EP

TEM

BE

R 2

010

A


Appendix 14.H. Maps

!(5

!(8

!(3

!(1

!(7!(6

!(2

!(4

Level 3, 86 Customhouse Quay, Wellington 6011,

PO Box 10-283, Wellington 6143NEW ZEALAND

Tel +64 4 473 4265Fax +64 4 473 3369

COPYRIGHT

No DATE DRAWN AMENDMENT

CLIENT

PROJECT

DRAWN

DESIGNED

DATE

DESIGN REVIEW

REVIEWEDPROJECT MANAGER

APPROVEDPROJECT DIRECTOR

TITLE

SCALE @ A3 SKM PROJECT No DRAWING No AMDT

[

The concepts and information containedin this document are the copyright ofSinclair Knight Merz Ltd. Use or copying of the document in whole or inpart without the written permission ofSinclair Knight Merz Ltd. constitutesan infringement of copyright.

MAP 1CATCHMENT LAND COVER

NEW ZEALAND TRANSPORT AGENCY

TRANSMISSION GULLY PROJECTTECHNICAL REPORT 14

1:100,000 AE03778

SJB

CMM

MAY 2011

Land cover

bare

bush

crops

fallow

parkland/gardens

pasture/grassland

plantation forest

water

wetland

urban

Existing Roads

Proposed Road

0 1 2 3 4km

Catchments

Whareroa

Te Puka / Wainui

Horokiri

Ration

Pauatahanui

Duck

Kenepuru

Porirua

!(1

!(6!(5!(4!(3!(2

!(7!(8

!(5

!(8

!(3

!(1

!(7!(6

!(2

!(4

··

1

··

58

··

2

Level 3, 86 Customhouse HouseWellington 6011


Tel +64 4 473 4265Fax +64 4 473 3369

COPYRIGHT


CLIENT

PROJECT

DRAWN

DESIGNED

DATE

DESIGN REVIEW



TITLE


[


MAP 2SOIL DRAINAGE CLASSES


TRANSMISSION GULLY AEEWORKSTREAM 4

1:100,000 AE03778

KWH

CMM

NOV 2010

Soil Drainage Class

A

B

C

D

0 1 2 3 4km

Catchments

Whareroa

Te Puka / Wainui

Horokiri

Ration

Pauatahanui

Duck

Kenepuru

Porirua

!(1

!(6!(5!(4!(3!(2

!(7!(8

!(5

!(8

!(3

!(1

!(7!(6

!(2

!(4

··

1

··

58

··

2

Level 3, 86 Customhouse Quay, Welli ngton 6011,


Tel +64 4 473 4265Fax +64 4 473 3369

COPYRIGHT


CLIENT

PROJECT

DRAWN

DESIGNED

DATE

DESIGN REVIEW



TITLE


[

The concepts and information containedin this document are the copyrig ht ofSinclair Kn ight M erz Ltd. Use or copying of the document in whole o r inpart without t he written pe rmission ofSinclair Kn ight M erz Ltd. constitutesan infr ingement of copyright.

MAP 3STREAM CATCHMENTS



1:100,000 AE03778

SJB

CMM

NOV 2010

Streams

State Highways

Proposed Road Alignment

0 1 2 3 4 5km

CatchmentsWhareroa 1572 Ha

Te Puka / Wainui 830 Ha

Horokiri 3306 Ha

Ration 680 Ha

Pauatahanui 4170 Ha

Duck 1030 Ha

Kenepuru 1265 Ha

Porirua 4107 Ha

!(1

!(6!(5!(4!(3!(2

!(7!(8

Te O

nepoto B

ay

Pauatahanui

Wellington Harbour

Pukerua Bay

Titahi Bay

Wha

rero

a

Bea

ch

!

!

!

!

!

!

!

!!

!

!

! !

!!

!

!

!

!

!

!

!

!

! !

!

!

!

!

!

!

!!

Tawa

Oriwa

Linden

Makara

Otaki 1

Manakau

McIntosh

Warwicks

Waikanae

Taungata

Mangaone

Arawhata

Judgeford

Salamanca

Reikorangi

Whenua Tapu

Otaki Depot

Kapakapanui

Blue Gum Spur

Otaki Temuera

Mt Holdsworth

Kapiti Island

Te Horo Jonelle

Paraparaumu Aero

Paekakariki Hill

Te Horo Longcroft

Seton Nossiter Park

Wellington, Thorndon

Mill Creek Reservoir

Horokiri at Grenlo

Pauatahanui at Gorge

Horokiri at Snodgrass

Porirua at Town Centre

[! Flow Gauging Stations

! Rainfall Gauging Stations

0 5 10 15km

Level 3, 86 Customhouse QuayWelli ngton 6011


Tel +64 4 473 4265Fax +64 4 473 3369

COPYRIGHT


CLIENT

PROJECT

DRAWN

DESIGNED

DATE

DESIGN REVIEW



TITLE


The concepts and information containedin this document are the copyrig ht ofSinclair Kn ight M erz Ltd. Use or copying of the document in whole o r inpart without t he written pe rmission ofSinclair Kn ight M erz Ltd. constitutesan infr ingement of copyright.

MAP 4RAINFALL AND FLOW GAUGING STATIONS



1:275,000 AE03778

KWH

CMM

NOV 2010

SH 58

BRAD

EY R

OAD

JOSEPH BANKS DRIVE

LANYON PLACE

GRAYS ROAD

PAR

EMATA H

AYWAR

DS R

OAD

VOYAGER WAY

SH 58

Level 3, 86 Customhouse QuayWellington 6011


Tel +64 4 473 4265Fax +64 4 473 3369

COPYRIGHT


CLIENT

PROJECT

DRAWN

DESIGNED

DATE

DESIGN REVIEW



TITLE



MAP 5APAUATAHANUI PEAKINUNDATION DEPTHS

NEW ZEALAND TRANSPORT AGENCYTRANSMISSION GULLY PROJECTTECHNICAL REPORT 14

1:5,000 AE03778

KWH

CMM

MAY 2011

[

0 100 200 300m

FILE

NA

ME

: I:\

AE

NV

W\P

roje

cts\

AE

0377

8\D

eliv

erab

les\

Fina

l Col

late

d R

epor

t WS

4\M

aste

r\Pla

n S

et\M

XD

s\M

ap6a

_Pau

atah

anui

_Inu

ndat

ionP

eak_

Q10

.mxd

Modelled Stream Channel

0 - 0.15

0.15 - 0.3

0.3 - 0.5

0.5 - 0.75

0.75 - 1

>1

Existing Q10Inundation (m)

Buildings At Risk

SH 58

BRAD

EY R

OAD

GRAYS ROAD

JOSEPH BANKS DRIVE

NAVIGATION DRIVE

SAMW

ELL DR

IVE

LAN

YON

PLA

CE

THE M

AS

THEA

D

PETREL LANE

PAREMATA ROAD

SH 58



Tel +64 4 473 4265Fax +64 4 473 3369

COPYRIGHT


CLIENT

PROJECT

DRAWN

DESIGNED

DATE

DESIGN REVIEW



TITLE




1:6,250 AE03778

KWH

CMM

MAY 2011

[

0 100 200 300m

FILE

NA

ME

: I:\

AE

NV

W\P

roje

cts\

AE

0377

8\D

eliv

erab

les\

Fina

l Col

late

d R

epor

t WS

4\M

aste

r\Pla

n S

et\M

XD

s\M

ap6b

_Pau

atah

anui

_Inu

ndat

ionP

eak_

Q10

0.m

xd

MAP 5BPAUATAHANUI EXISTING PEAK INUNDATION DEPTHS


0 - 0.15

0.15 - 0.3

0.3 - 0.5

0.5 - 0.75

0.75 - 1

>1

Climate Change Q100Inundation (m)

Buildings At Risk

Existing Catchment

SH 58

BRAD

EY R

OAD

JOSEPH BANKS DRIVE

LANYON PLACE

GRAYS ROAD

PAR

EMATA H

AYWAR

DS R

OAD

VOYAGER WAY

SH 58



Tel +64 4 473 4265Fax +64 4 473 3369

COPYRIGHT


CLIENT

PROJECT

DRAWN

DESIGNED

DATE

DESIGN REVIEW



TITLE



MAP 6APAUATAHANUI FLOOD RISK



1:5,000 AE03778

KWH

CMM

MAY 2011

[

0 100 200 300m

FILE

NA

ME

: I:\

AE

NV

W\P

roje

cts\

AE

0377

8\D

eliv

erab

les\

Fina

l Col

late

d R

epor

t WS

4\M

aste

r\Pla

n S

et\M

XD

s\M

ap7a

_Pau

atah

anui

_Flo

odR

isk_

Q10

.mxd


0 - 0.15

0.15 - 0.3

0.3 - 0.5

0.5 - 0.75

0.75 - 1

>1

Q10 Inundation (m)With Project

Proposed Bridge


Proposed Laydown Area

Flood Mitigation Measures

SH 58

BRAD

EY R

OAD

JOSEPH BANKS DRIVE

LANYON PLACE

GRAYS ROAD

PAR

EMATA H

AYWAR

DS R

OAD

VOYAGER WAY

SH 58



Tel +64 4 473 4265Fax +64 4 473 3369

COPYRIGHT


CLIENT

PROJECT

DRAWN

DESIGNED

DATE

DESIGN REVIEW



TITLE



MAP 6BPAUATAHANUI FLOOD RISK



1:5,000 AE03778

KWH

CMM

MAY 2011

[

0 100 200 300m

FILE

NA

ME

: I:\

AE

NV

W\P

roje

cts\

AE

0377

8\D

eliv

erab

les\

Fina

l Col

late

d R

epor

t WS

4\M

aste

r\Pla

n S

et\M

XD

s\M

ap7b

_Pau

atah

anui

_Flo

odR

isk_

Q10

0.m

xd


0 - 0.15

0.15 - 0.3

0.3 - 0.5

0.5 - 0.75

0.75 - 1

>1

Q100 Climate ChangeInundation (m) With Project

Proposed Bridge




17

86

13

8890

17

92

SH 58

BRAD

EY R

OAD

JOSEPH BANKS DRIVE

LANYON PLACE

GRAYS ROAD

PAR

EMATA H

AYWAR

DS R

OAD

VOYAGER WAY

SH 58



Tel +64 4 473 4265Fax +64 4 473 3369

COPYRIGHT


CLIENT

PROJECT

DRAWN

DESIGNED

DATE

DESIGN REVIEW



TITLE



MAP 7COMPARISON OF PEAK WATERLEVELS IN PAUATAHANUI



1:5,000 AE03778

KWH

CMM

MAY 2011

[

0 100 200 300m

FILE

NA

ME

: I:\

AE

NV

W\P

roje

cts\

AE

0377

8\D

eliv

erab

les\

Fina

l Col

late

d R

epor

t WS

4\M

aste

r\Pla

n S

et\M

XD

s\M

ap8_

Pau

atah

anui

_Com

paris

on_Q

100.

mxd


Q100 Difference in PeakWater Surface Level (m)

Proposed Bridge




-0.15 - -0.01

Incr

ease

Dec

reas

e < -1-1 - -0.5-0.5 - -0.3-0.3 - -0.15

0.01 - 0.150.15 - 0.30.3 - 0.50.5 - 1> 1

Negatively Impacted Properties with Address90

With Project



Tel +64 4 473 4265Fax +64 4 473 3369

COPYRIGHT


CLIENT

PROJECT

DRAWN

DESIGNED

DATE

DESIGN REVIEW



TITLE



MAP 8AHOROKIRI PEAKINUNDATION DEPTHSUPPER CATCHMENT



1:10,000 AE03778

KWH

CMM

MAY 2011

[

0 200 400 600m

FILE

NA

ME

: I:\

AE

NV

W\P

roje

cts\

AE

0377

8\D

eliv

erab

les\

Fina

l Col

late

d R

epor

t WS

4\M

aste

r\Pla

n S

et\M

XD

s\M

ap9a

_Hor

okiri

_Inu

ndat

ionP

eak_

Q10

_UP

PE

R.m

xd


Existing Q10

Proposed Designation

0 - 0.15

0.15 - 0.3

0.3 - 0.5

0.5 - 1

> 1

Inundation (m)

PAEK

AKA

RIKI H

ILL RO

AD



Tel +64 4 473 4265Fax +64 4 473 3369

COPYRIGHT


CLIENT

PROJECT

DRAWN

DESIGNED

DATE

DESIGN REVIEW



TITLE



MAP 8BHOROKIRI PEAKINUNDATION DEPTHSMID CATCHMENT



1:10,000 AE03778

KWH

CMM

MAY 2011

[

0 200 400 600m

FILE

NA

ME

: I:\

AE

NV

W\P

roje

cts\

AE

0377

8\D

eliv

erab

les\

Fina

l Col

late

d R

epor

t WS

4\M

aste

r\Pla

n S

et\M

XD

s\M

ap9b

_Hor

okiri

_Inu

ndat

ionP

eak_

Q10

_MID

.mxd


Existing Q10


0 - 0.15

0.15 - 0.3

0.3 - 0.5

0.5 - 1

> 1

Inundation (m)

PAEK

AKAR

IKI H

ILL

RO

AD

GRAYS ROAD



Tel +64 4 473 4265Fax +64 4 473 3369

COPYRIGHT


CLIENT

PROJECT

DRAWN

DESIGNED

DATE

DESIGN REVIEW



TITLE



MAP 8CHOROKIRI PEAKINUNDATION DEPTHSLOWER CATCHMENT



1:10,000 AE03778

KWH

CMM

MAY 2011

[

0 200 400 600m

FILE

NA

ME

: I:\

AE

NV

W\P

roje

cts\

AE

0377

8\D

eliv

erab

les\

Fina

l Col

late

d R

epor

t WS

4\M

aste

r\Pla

n S

et\M

XD

s\M

ap9c

_Hor

okiri

_Inu

ndat

ionP

eak_

Q10

_LO

WE

R.m

xd


Existing Q10Inundation (m)


0 - 0.15

0.15 - 0.3

0.3 - 0.5

0.5 - 1

> 1

Buildings At Risk



Tel +64 4 473 4265Fax +64 4 473 3369

COPYRIGHT


CLIENT

PROJECT

DRAWN

DESIGNED

DATE

DESIGN REVIEW



TITLE



MAP 8DHOROKIRI PEAKINUNDATION DEPTHSUPPER CATCHMENT



1:10,000 AE03778

KWH

CMM

MAY 2011

[

0 200 400 600m


Climate Change Q100


0 - 0.15

0.15 - 0.3

0.3 - 0.5

0.5 - 1

> 1

Inundation (m)

PAEK

AKA

RIKI H

ILL RO

AD



Tel +64 4 473 4265Fax +64 4 473 3369

COPYRIGHT


CLIENT

PROJECT

DRAWN

DESIGNED

DATE

DESIGN REVIEW



TITLE



MAP 8EHOROKIRI PEAKINUNDATION DEPTHSMID CATCHMENT



1:10,000 AE03778

KWH

CMM

MAY 2011

[

0 200 400 600m




0 - 0.15

0.15 - 0.3

0.3 - 0.5

0.5 - 1

> 1

Buildings At Risk

PAEK

AKAR

IKI H

ILL

RO

AD

GRAYS ROAD



Tel +64 4 473 4265Fax +64 4 473 3369

COPYRIGHT


CLIENT

PROJECT

DRAWN

DESIGNED

DATE

DESIGN REVIEW



TITLE



MAP 8FHOROKIRI PEAKINUNDATION DEPTHSLOWER CATCHMENT



1:10,000 AE03778

KWH

CMM

MAY 2011

[

0 200 400 600m




0 - 0.15

0.15 - 0.3

0.3 - 0.5

0.5 - 1

> 1

Buildings At Risk

SH 1

TILL

EY R

OAD

WEL

LING

TON

RO

AD

TE MITI STREET

APER

AHAM

A ST

REET

TARAWA STREET

HAUM

IA S

TREE

T

MUTU ROAD

MIRIONA GROVE



Tel +64 4 473 4265Fax +64 4 473 3369

COPYRIGHT


CLIENT

PROJECT

DRAWN

DESIGNED

DATE

DESIGN REVIEW



TITLE



MAP 9ATE PUKA / WAINUI PEAKINUNDATION DEPTHS


1:6,000 AE03778

KWH

CMM

MAY 2011

[

0 100 200 300 400m


Existing Q10


0 - 0.15

0.15 - 0.3

0.3 - 0.5

0.5 - 1

> 1

Inundation (m)

SH 1

TILL

EY R

OAD

WEL

LING

TON

RO

AD

TE MITI STREET

APER

AHAM

A ST

REET

TARAWA STREET

HAUM

IA S

TREE

T

MUTU ROAD

MIRIONA GROVE



Tel +64 4 473 4265Fax +64 4 473 3369

COPYRIGHT


CLIENT

PROJECT

DRAWN

DESIGNED

DATE

DESIGN REVIEW



TITLE



MAP 9BTE PUKA / WAINUI PEAKINUNDATION DEPTHS


1:6,000 AE03778

KWH

CMM

MAY 2011

[

0 100 200 300 400m


Climate Change Q100


0 - 0.15

0.15 - 0.3

0.3 - 0.5

0.5 - 1

> 1

Inundation (m)

Appendix 14.A. Topographic Data for Hydraulic Models

Documents

Transcript of Appendix 14.A. Topographic Data for Hydraulic Models